Bump versions.errorprone from 2.8.0 to 2.8.1 (#2386)

Bumps `versions.errorprone` from 2.8.0 to 2.8.1.

Updates `error_prone_core` from 2.8.0 to 2.8.1
- [Release notes](https://github.com/google/error-prone/releases)
- [Commits](google/error-prone@v2.8.0...v2.8.1)

Updates `error_prone_test_helpers` from 2.8.0 to 2.8.1
- [Release notes](https://github.com/google/error-prone/releases)
- [Commits](google/error-prone@v2.8.0...v2.8.1)

---
updated-dependencies:
- dependency-name: com.google.errorprone:error_prone_core
  dependency-type: direct:production
  update-type: version-update:semver-patch
- dependency-name: com.google.errorprone:error_prone_test_helpers
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

gradle/dependencies.gradle

@@ -6,7 +6,7 @@ def versions = [:]
 
 versions.bytebuddy = '1.11.9'
 versions.junitJupiter = '5.7.2'
-versions.errorprone = '2.8.0'
+versions.errorprone = '2.8.1'
 
 libraries.junit4 = 'junit:junit:4.13.2'
 libraries.junitJupiterApi = "org.junit.jupiter:junit-jupiter-api:${versions.junitJupiter}"