Bump com.diffplug.spotless from 6.19.0 to 6.20.0

Bumps com.diffplug.spotless from 6.19.0 to 6.20.0.

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

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

Author: dependabot[bot]

build.gradle.kts

@@ -10,7 +10,7 @@ plugins {
     signing
     id("io.gitlab.arturbosch.detekt") version "1.18.0"
     id("com.android.library") version "7.4.2"
-    id("com.diffplug.spotless") version "6.19.0"
+    id("com.diffplug.spotless") version "6.20.0"
 }