Update dependency org.jetbrains.dokka:dokka-gradle-plugin to v1.6.20 (#…

…66)

Co-authored-by: Renovate Bot <bot@renovateapp.com>

build.gradle

@@ -15,7 +15,7 @@ buildscript {
         classpath "de.mannodermaus.gradle.plugins:android-junit5:1.8.2.0"
         classpath "com.hiya:jacoco-android:0.2"
         classpath "org.jmailen.gradle:kotlinter-gradle:3.10.0"
-        classpath "org.jetbrains.dokka:dokka-gradle-plugin:1.6.10"
+        classpath "org.jetbrains.dokka:dokka-gradle-plugin:1.6.20"
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files
     }