Move handwritten libraries to use version of maven-javadoc-plugin from java-shared-config

[alicejli]

See #661

[alicejli]

@suztomo fixed the bigtable breakage by removing their explicit version declaration of the maven-javadoc-plugin to rely on the java-shared-config version (which has been reverted back to 3.5.0): googleapis/java-bigtable#1950

This will need to be replicated for the following handwritten libraries:

1. google-cloud-bigquerystorage
2. google-cloud-bigquery
3. google-cloud-firestore
4. google-cloud-logging
5. google-cloud-logging-logback
6. google-cloud-pubsub
7. google-cloud-pubsublite
8. google-cloud-spanner
9. google-cloud-spanner-jdbc