chore: sync tables without acquiring read lock the whole time

[ashwanthgoli]

What this PR does / why we need it:

Table manager and Table grab a read lock for the entire duration when syncing tables and index sets respectively, this can prevent new tables and new indexsets from getting initialised while the rlock is held. This pr tries to reduce the possibility of sync calls affecting query time table and indexset initialisation by grabbing the lock only for accessing protected resource during the sync loop

Which issue(s) this PR fixes:
Fixes #

Special notes for your reviewer:

Checklist

• Reviewed the CONTRIBUTING.md guide (required)
• Documentation added
• Tests updated
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[JoaoBraveCoding]

lgtm, just one question. Is it still safe to call indexSet.Sync or table.Sync without holding a lock over t.indexSetMtx or tm.tablesMtx respectively? That's the only thing that poped into my head while reviewing

[JoaoBraveCoding]

lgtm but I haven't tested it

[ashwanthgoli]

Thanks @JoaoBraveCoding!
i had similar doubts, but the individual tables and indexsets are internally protected by their own lock. ForConcurrent which is used for querying does not hold the lock on table and indexset list either.

I have been running these change in our dev and ops env, no issues so far