dependabot: bump com.diffplug.spotless from 8.2.0 to 8.2.1

Bumps com.diffplug.spotless from 8.2.0 to 8.2.1.

---
updated-dependencies:
- dependency-name: com.diffplug.spotless
  dependency-version: 8.2.1
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

gradle/libs.versions.toml

@@ -1,5 +1,5 @@
 [versions]
-spotless = "8.2.0"
+spotless = "8.2.1"
 errorprone-plugin = "5.0.0"
 errorprone-core = "2.46.0"
 nullaway = "0.13.1"