docs(ref): Add missing config env variables (#17345)

### What does this PR try to resolve?

As identified at
#17335 (comment)

### How to test and review this PR?

Author: weihanglo

doc/book/src/reference/environment-variables.md

@@ -88,6 +88,7 @@ See the [configuration chapter][config-env] for more details.
 In summary, the supported environment variables are:
 
 * `CARGO_ALIAS_<name>` --- Command aliases, see [`alias`].
+* `CARGO_BUILD_WARNINGS` --- The effective level of lint warnings for local packages, see [`build.warnings`].
 * `CARGO_BUILD_JOBS` --- Number of parallel jobs, see [`build.jobs`].
 * `CARGO_BUILD_RUSTC` --- The `rustc` executable, see [`build.rustc`].
 * `CARGO_BUILD_RUSTC_WRAPPER` --- The `rustc` wrapper, see [`build.rustc-wrapper`].
@@ -102,6 +103,7 @@ In summary, the supported environment variables are:
 * `CARGO_BUILD_DEP_INFO_BASEDIR` --- Dep-info relative directory, see [`build.dep-info-basedir`].
 * `CARGO_CACHE_AUTO_CLEAN_FREQUENCY` --- Configures how often automatic cache cleaning runs, see [`cache.auto-clean-frequency`].
 * `CARGO_CARGO_NEW_VCS` --- The default source control system with [`cargo new`], see [`cargo-new.vcs`].
+* `CARGO_CREDENTIAL_ALIAS_<name>` --- Credential provider aliases, see [`credential-alias`].
 * `CARGO_FUTURE_INCOMPAT_REPORT_FREQUENCY` --- How often we should generate a future incompat report notification, see [`future-incompat-report.frequency`].
 * `CARGO_HTTP_DEBUG` --- Enables HTTP debugging, see [`http.debug`].
 * `CARGO_HTTP_PROXY` --- Enables HTTP proxy, see [`http.proxy`].
@@ -132,18 +134,25 @@ In summary, the supported environment variables are:
 * `CARGO_REGISTRIES_<name>_CREDENTIAL_PROVIDER` --- Credential provider for a registry, see [`registries.<name>.credential-provider`].
 * `CARGO_REGISTRIES_<name>_INDEX` --- URL of a registry index, see [`registries.<name>.index`].
 * `CARGO_REGISTRIES_<name>_TOKEN` --- Authentication token of a registry, see [`registries.<name>.token`].
+* `CARGO_REGISTRIES_CRATES_IO_PROTOCOL` --- The protocol used to access [crates.io], see [`registries.crates-io.protocol`].
 * `CARGO_REGISTRY_CREDENTIAL_PROVIDER` --- Credential provider for [crates.io], see [`registry.credential-provider`].
 * `CARGO_REGISTRY_DEFAULT` --- Default registry for the `--registry` flag, see [`registry.default`].
 * `CARGO_REGISTRY_GLOBAL_CREDENTIAL_PROVIDERS` --- Credential providers for registries that do not have a specific provider defined. See [`registry.global-credential-providers`].
 * `CARGO_REGISTRY_TOKEN` --- Authentication token for [crates.io], see [`registry.token`].
+* `CARGO_RESOLVER_INCOMPATIBLE_RUST_VERSIONS` --- How incompatible Rust versions are treated during dependency resolution, see [`resolver.incompatible-rust-versions`].
+* `CARGO_RESOLVER_LOCKFILE_PATH` --- The path to the lockfile, see [`resolver.lockfile-path`].
 * `CARGO_TARGET_<triple>_LINKER` --- The linker to use, see [`target.<triple>.linker`]. The triple must be [converted to uppercase and underscores](config.md#environment-variables).
 * `CARGO_TARGET_<triple>_RUNNER` --- The executable runner, see [`target.<triple>.runner`].
 * `CARGO_TARGET_<triple>_RUSTFLAGS` --- Extra `rustc` flags for a target, see [`target.<triple>.rustflags`].
+* `CARGO_TARGET_<triple>_RUSTDOCFLAGS` --- Extra `rustdoc` flags for a target, see [`target.<triple>.rustdocflags`].
 * `CARGO_TERM_QUIET` --- Quiet mode, see [`term.quiet`].
 * `CARGO_TERM_VERBOSE` --- The default terminal verbosity, see [`term.verbose`].
 * `CARGO_TERM_COLOR` --- The default color mode, see [`term.color`].
+* `CARGO_TERM_HYPERLINKS` --- Whether hyperlinks are used in the terminal, see [`term.hyperlinks`].
+* `CARGO_TERM_UNICODE` --- Whether terminal output can use non-ASCII Unicode characters, see [`term.unicode`].
 * `CARGO_TERM_PROGRESS_WHEN` --- The default progress bar showing mode, see [`term.progress.when`].
 * `CARGO_TERM_PROGRESS_WIDTH` --- The default progress bar width, see [`term.progress.width`].
+* `CARGO_TERM_PROGRESS_TERM_INTEGRATION` --- Whether progress is reported to the terminal emulator, see [`term.progress.term-integration`].
 
 [`cargo doc`]: ../commands/cargo-doc.md
 [`cargo install`]: ../commands/cargo-install.md
@@ -154,6 +163,7 @@ In summary, the supported environment variables are:
 [crates.io]: https://crates.io/
 [incremental compilation]: profiles.md#incremental
 [`alias`]: config.md#alias
+[`build.warnings`]: config.md#buildwarnings
 [`build.jobs`]: config.md#buildjobs
 [`build.rustc`]: config.md#buildrustc
 [`build.rustc-wrapper`]: config.md#buildrustc-wrapper
@@ -166,6 +176,7 @@ In summary, the supported environment variables are:
 [`build.rustdocflags`]: config.md#buildrustdocflags
 [`build.incremental`]: config.md#buildincremental
 [`build.dep-info-basedir`]: config.md#builddep-info-basedir
+[`credential-alias`]: config.md#credential-alias
 [`doc.browser`]: config.md#docbrowser
 [`cache.auto-clean-frequency`]: config.md#cacheauto-clean-frequency
 [`cargo-new.name`]: config.md#cargo-newname
@@ -198,21 +209,28 @@ In summary, the supported environment variables are:
 [`profile.<name>.rpath`]: config.md#profilenamerpath
 [`profile.<name>.split-debuginfo`]: config.md#profilenamesplit-debuginfo
 [`profile.<name>.strip`]: config.md#profilenamestrip
+[`resolver.lockfile-path`]: config.md#resolverlockfile-path
+[`resolver.incompatible-rust-versions`]: config.md#resolverincompatible-rust-versions
 [`registries.<name>.credential-provider`]: config.md#registriesnamecredential-provider
 [`registries.<name>.index`]: config.md#registriesnameindex
 [`registries.<name>.token`]: config.md#registriesnametoken
+[`registries.crates-io.protocol`]: config.md#registriescrates-ioprotocol
 [`registry.credential-provider`]: config.md#registrycredential-provider
 [`registry.default`]: config.md#registrydefault
 [`registry.global-credential-providers`]: config.md#registryglobal-credential-providers
 [`registry.token`]: config.md#registrytoken
 [`target.<triple>.linker`]: config.md#targettriplelinker
 [`target.<triple>.runner`]: config.md#targettriplerunner
 [`target.<triple>.rustflags`]: config.md#targettriplerustflags
+[`target.<triple>.rustdocflags`]: config.md#targettriplerustdocflags
 [`term.quiet`]: config.md#termquiet
 [`term.verbose`]: config.md#termverbose
 [`term.color`]: config.md#termcolor
+[`term.hyperlinks`]: config.md#termhyperlinks
+[`term.unicode`]: config.md#termunicode
 [`term.progress.when`]: config.md#termprogresswhen
 [`term.progress.width`]: config.md#termprogresswidth
+[`term.progress.term-integration`]: config.md#termprogressterm-integration
 
 ## Environment variables Cargo sets for crates