Cleanup unused branches

[dblock]

Coming from opensearch-project/opensearch-clients#64, cleanup unused branches.

For some unused branches we probably want to save state, so maybe note the last revision of any branch being deleted in this issue as it's being closed.

[saimedhi]

Hey Soner (@shyim),

I believe we can remove the branches 2.x and add-client-docs. What are your thoughts on this?

Thanks!

[shyim]

yes and i would delete gh-pages. github pages are done by actions not by a branch

[saimedhi]

@gaiksaya, could you please remove branches 2.x, add-client-docs, gh-pages? Thanks!

[gaiksaya]

Deleted above mentioned branches. Thanks @saimedhi for 2PR.