Bump antlr4 from 4.13.1 to 4.13.2 in /_scripts/templates/Dart (#4192)

Bumps [antlr4](https://github.com/antlr/antlr4) from 4.13.1 to 4.13.2.
- [Release notes](https://github.com/antlr/antlr4/releases)
- [Changelog](https://github.com/antlr/antlr4/blob/dev/CHANGES.txt)
- [Commits](antlr/antlr4@4.13.1...4.13.2)

---
updated-dependencies:
- dependency-name: antlr4
  dependency-type: direct:production
  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>

_scripts/templates/Dart/pubspec.yaml

@@ -4,7 +4,7 @@ description: A sample command-line application.
 environment:
   sdk: '>=2.12.0 <3.0.0'
 dependencies:
-  antlr4: 4.13.1
+  antlr4: 4.13.2
 dev_dependencies:
   pedantic: ^1.9.0
   test: ^1.14.4