Bump org.jetbrains.dokka from 1.8.10 to 1.8.20 (#682)

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] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

build.gradle.kts

@@ -6,7 +6,7 @@ plugins {
     id("com.palantir.git-version") version "3.0.0"
 
     // Documentation
-    id("org.jetbrains.dokka") version "1.8.10"
+    id("org.jetbrains.dokka") version "1.8.20"
 
     // Style checking
     id("com.diffplug.spotless") version "6.18.0"