Bump detekt-gradle-plugin from 1.20.0 to 1.21.0

Bumps [detekt-gradle-plugin](https://github.com/detekt/detekt) from 1.20.0 to 1.21.0.
- [Release notes](https://github.com/detekt/detekt/releases)
- [Commits](https://github.com/detekt/detekt/compare/v1.20.0...v1.21.0)

---
updated-dependencies:
- dependency-name: io.gitlab.arturbosch.detekt:detekt-gradle-plugin
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

build.gradle

@@ -38,7 +38,7 @@ buildscript {
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:${kotlinVersion}"
         classpath "org.jetbrains.kotlin:kotlin-serialization:${kotlinVersion}"
         classpath 'gradle.plugin.com.github.spotbugs.snom:spotbugs-gradle-plugin:4.7.5'
-        classpath "io.gitlab.arturbosch.detekt:detekt-gradle-plugin:1.20.0"
+        classpath "io.gitlab.arturbosch.detekt:detekt-gradle-plugin:1.21.0"
         classpath "org.jlleitschuh.gradle:ktlint-gradle:10.3.0"
 
         // NOTE: Do not place your application dependencies here; they belong