Bump org.jetbrains.dokka:dokka-maven-plugin from 1.9.10 to 1.9.20 (#922)

Bumps [org.jetbrains.dokka:dokka-maven-plugin](https://github.com/Kotlin/dokka) from 1.9.10 to 1.9.20.
- [Release notes](https://github.com/Kotlin/dokka/releases)
- [Commits](https://github.com/Kotlin/dokka/commits)

---
updated-dependencies:
- dependency-name: org.jetbrains.dokka:dokka-maven-plugin
  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>

pom.xml

@@ -84,7 +84,7 @@
  <maven-compiler-plugin.version>3.12.1</maven-compiler-plugin.version>
  <maven-javadoc-plugin.version>3.6.3</maven-javadoc-plugin.version>
  <maven-source-plugin.version>3.3.0</maven-source-plugin.version>
- <dokka.version>1.9.10</dokka.version>
+ <dokka.version>1.9.20</dokka.version>
  <animal-sniffer.version>1.23</animal-sniffer.version>
  <api-level-24.version>7.0_r2</api-level-24.version>
  <nexus-staging-maven-plugin.version>1.6.13</nexus-staging-maven-plugin.version>