chore(deps): bump proc-macro2 from 1.0.40 to 1.0.42

Bumps [proc-macro2](https://github.com/dtolnay/proc-macro2) from 1.0.40 to 1.0.42.
- [Release notes](https://github.com/dtolnay/proc-macro2/releases)
- [Commits](https://github.com/dtolnay/proc-macro2/compare/1.0.40...1.0.42)

---
updated-dependencies:
- dependency-name: proc-macro2
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

Cargo.lock

@@ -849,9 +849,9 @@ dependencies = [
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.40"
+version = "1.0.42"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "dd96a1e8ed2596c337f8eae5f24924ec83f5ad5ab21ea8e455d3566c69fbcaf7"
+checksum = "c278e965f1d8cf32d6e0e96de3d3e79712178ae67986d9cf9151f51e95aac89b"
 dependencies = [
  "unicode-ident",
 ]