Add missing javadoc and sources jar publication

That was missed during 92509ad400 on
adding commit.

libraries/tools/kotlin-gradle-build-metrics/build.gradle.kts

@@ -32,3 +32,5 @@ publishing {
         }
     }
 }
+sourcesJar()
+javadocJar()

libraries/tools/kotlin-gradle-statistics/build.gradle.kts

@@ -32,3 +32,5 @@ publishing {
         }
     }
 }
+sourcesJar()
+javadocJar()