Bump com.uber.nullaway:nullaway in the all-minor group

Bumps the all-minor group with 1 update: [com.uber.nullaway:nullaway](https://github.com/uber/NullAway).


Updates `com.uber.nullaway:nullaway` from 0.12.14 to 0.12.15
- [Release notes](https://github.com/uber/NullAway/releases)
- [Changelog](https://github.com/uber/NullAway/blob/master/CHANGELOG.md)
- [Commits](uber/NullAway@v0.12.14...v0.12.15)

---
updated-dependencies:
- dependency-name: com.uber.nullaway:nullaway
  dependency-version: 0.12.15
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: all-minor
...

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

Author: dependabot[bot]

gradle/libs.versions.toml

@@ -3,7 +3,7 @@
 errorprone = "2.45.0"
 junitJupiter = "6.0.1"
 ktlint = "1.8.0"
-nullaway = "0.12.14"
+nullaway = "0.12.15"
 
 [libraries]
 errorprone-checkApi = { module = "com.google.errorprone:error_prone_check_api", version.ref = "errorprone" }