KAFKA-18828: Update share group metrics per new init and call mechanism.

[smjn]

• Due to recent changes in the way group count metrics are initialized and updated, the current share group count code has become obsolete as well as non-functional.
• The update method for the share group count which should be called from ShareGroup cannot be called either. This is because the constructor has been changed to NOT accept the GroupCoordinatorShardMetrics ref.
• In this PR, we remedy the situation by bringing share group count code at par with consumer and streams groups.
• Additionally the metric name for share groups with group state attributes was not aligned with streams and consumer groups as mentioned in KAFKA-17367: Share coordinator impl. Broker side code. [2/N] #17011 (comment). This PR aligns them too.

Ref:
KAFKA-18655: Implement the consumer group size counter with scheduled task (#18717)

[apoorvmittal10]

@smjn While you are fixing the group-count can you please also take at following conversation and add the minor change in the PR. We shall correct the KIP as well later.

[AndrewJSchofield]

Thanks for the PR. lgtm. I have updated the KIP accordingly.