Fix semicolon_in_expressions_from_macros errors on nightly

[ChronicallyJD]

Summary

Newer Rust toolchains promote the semicolon_in_expressions_from_macros future-incompatibility lint (rust-lang/rust#79813) to a hard, deny-by-default error. This breaks bail!(...) invocations used in expression position (the tail of a block or match arm).

The verify package can build workflow (.github/workflows/package-test.yaml) builds with nightly (rustup.sh nightly, cargo +nightly install --path cargo-pgrx, cargo +nightly package), so it fails on this on current develop, independent of any feature work.

Fix

Add trailing semicolons so the macro invocations are statements rather than tail expressions:

• pgrx-sql-entity-graph/src/section.rs (match-arm block)
• cargo-pgrx/src/command/install.rs (let ... else block)
• cargo-pgrx/src/object_utils.rs (bare match arm, wrapped in a block)

No behavior change: bail! diverges in all three cases.

Testing

• Reproduced on nightly (rustc 1.99.0-nightly): cargo +nightly build -p cargo-pgrx --locked failed with the lint; after the fix it builds clean.
• Full nightly check across every crate the package workflow builds is clean:
  cargo +nightly check -p pgrx-pg-config -p pgrx-bindgen -p pgrx-sql-entity-graph -p pgrx-macros -p pgrx-pg-sys -p pgrx -p pgrx-bench -p pgrx-tests -p cargo-pgrx --features pg18 --no-default-features.
• No regression on the pinned toolchain (1.96.0): cargo build -p cargo-pgrx and cargo test -p pgrx-sql-entity-graph pass; cargo fmt --all --check and cargo clippy -p pgrx-sql-entity-graph -- -Dwarnings are clean.