Bump org.jetbrains.dokka from 1.8.10 to 1.8.20

Bumps [org.jetbrains.dokka](https://github.com/Kotlin/dokka) from 1.8.10 to 1.8.20.
- [Release notes](https://github.com/Kotlin/dokka/releases)
- [Commits](https://github.com/Kotlin/dokka/commits)

---
updated-dependencies:
- dependency-name: org.jetbrains.dokka
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

lib/build.gradle.kts

@@ -3,7 +3,7 @@ plugins {
     id("kotlin-android")
     id("maven-publish")
     id("signing")
-    id("org.jetbrains.dokka") version "1.8.10"
+    id("org.jetbrains.dokka") version "1.8.20"
 }