Merge pull request #11580 from nextcloud/dependabot/gradle/kotlin_version-1.8.21

Build(deps): Bump kotlin_version from 1.8.10 to 1.8.21

build.gradle

@@ -3,7 +3,7 @@ buildscript {
         androidPluginVersion = '7.4.2'
         appCompatVersion = '1.6.1'
         jacoco_version = '0.8.9'
-        kotlin_version = '1.8.10'
+        kotlin_version = '1.8.21'
         androidxTestVersion = "1.4.0"
         daggerVersion = "2.45"
         markwonVersion = "4.6.2"