Bump com.google.testing.compile:compile-testing from 0.19 to 0.21.0

Bumps [com.google.testing.compile:compile-testing](https://github.com/google/compile-testing) from 0.19 to 0.21.0.
- [Release notes](https://github.com/google/compile-testing/releases)
- [Commits](google/compile-testing@compile-testing-0.19...v0.21.0)

---
updated-dependencies:
- dependency-name: com.google.testing.compile:compile-testing
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

build.gradle.kts

@@ -151,7 +151,7 @@ configure(libs) {
             dependency("com.github.spotbugs:spotbugs:4.8.3")
             dependency("com.github.tomakehurst:wiremock:3.0.1")
             dependency("com.google.inject:guice:7.0.0")
-            dependency("com.google.testing.compile:compile-testing:0.19")
+            dependency("com.google.testing.compile:compile-testing:0.21.0")
             dependency("com.puppycrawl.tools:checkstyle:10.17.0")
             dependency("com.squareup.retrofit2:retrofit:2.11.0")
             dependency("commons-io:commons-io:2.16.1")