Bump proc-macro2 from 1.0.49 to 1.0.52 (#508)

Bumps [proc-macro2](https://github.com/dtolnay/proc-macro2) from 1.0.49 to 1.0.52.
- [Release notes](https://github.com/dtolnay/proc-macro2/releases)
- [Commits](https://github.com/dtolnay/proc-macro2/compare/1.0.49...1.0.52)

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

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Cargo.lock

@@ -1486,9 +1486,9 @@ dependencies = [
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.49"
+version = "1.0.52"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "57a8eca9f9c4ffde41714334dee777596264c7825420f521abc92b5b5deb63a5"
+checksum = "1d0e1ae9e836cc3beddd63db0df682593d7e2d3d891ae8c9083d2113e1744224"
 dependencies = [
  "unicode-ident",
 ]