[FLINK-31676][Connector/Pulsar] Replace Shaded Guava from Flink with Shaded Guava from Pulsar

[MartijnVisser]

Purpose of the change

• Replace dependency on Flink-Shaded for connectors, since externalized connectors shouldn't rely on Flink-Shaded

Brief change log

• Removed all occurrences of org.apache.flink.shaded.guava30.com with org.apache.pulsar.shade.com

Verifying this change

This change is a trivial rework / code cleanup without any test coverage.

Significant changes

(Please check any boxes [x] if the answer is "yes". You can first publish the PR and check them afterwards, for
convenience.)

• Dependencies have been added or upgraded
• Public API has been changed (Public API is any class annotated with @Public(Evolving))
• Serializers have been changed
• New feature has been introduced
  • If yes, how is this documented? (not applicable / docs / JavaDocs / not documented)

[tisonkun]

I don't see a pom.xml change, how can we prevent dependencies on Flink Shade predictably?

[MartijnVisser]

how can we prevent dependencies on Flink Shade predictably?

I don't think we can; it's a transitive dependency of Flink, which is needed in order to build/test the connector.

[tisonkun]

Thanks for your explanation! Let's fix these occurrences then.

[syhily]

flink-shade is an transitive dependency. We can't prevent the use of it, but we can ask others to use Pulsar's shaded Guava when review the PRs.