fix(package): update tracking issue for --message-format (#15354)

Went ahead and created a new tracking issue
<#15353>.

Author: epage

Diff for: src/bin/cargo/commands/package.rs

@@ -86,7 +86,7 @@ pub fn exec(gctx: &mut GlobalContext, args: &ArgMatches) -> CliResult {
 
     let fmt = if let Some(fmt) = args._value_of("message-format") {
         gctx.cli_unstable()
-            .fail_if_stable_opt("--message-format", 11666)?;
+            .fail_if_stable_opt("--message-format", 15353)?;
         fmt.parse()?
     } else {
         PackageMessageFormat::Human

Diff for: src/doc/src/reference/unstable.md

@@ -1892,7 +1892,8 @@ Specify which packages participate in [feature unification](../reference/feature
 
 ## Package message format
 
-* Tracking Issue: [#11666](https://github.com/rust-lang/cargo/issues/11666)
+* Original Issue: [#11666](https://github.com/rust-lang/cargo/issues/11666)
+* Tracking Issue: [#15353](https://github.com/rust-lang/cargo/issues/15353)
 
 The `--message-format` flag in `cargo package` controls the output message format.
 Currently, it only works with the `--list` flag and affects the file listing format,

Diff for: tests/testsuite/package_message_format.rs

@@ -26,7 +26,7 @@ fn gated() {
         .with_status(101)
         .with_stderr_data(str![[r#"
 [ERROR] the `--message-format` flag is unstable, pass `-Z unstable-options` to enable it
-See https://github.com/rust-lang/cargo/issues/11666 for more information about the `--message-format` flag.
+See https://github.com/rust-lang/cargo/issues/15353 for more information about the `--message-format` flag.
 
 "#]])
         .run();