core/filtermaps: fix range delete deadlock

[zsfelfoldi]

This PR fixes a deadlock situation is deleteTailEpoch that might arise when range delete is running in iterator based fallback mode (either using leveldb database or the hashdb state storage scheme). In this case a stopCb callback is called periodically that does check events, including matcher sync requests, in which case it tries to acquire indexLock for write access, while deleteTailEpoch already held it for read access. This callback is called in every other case with indexLock unlocked so this PR unlocks it while the actual data removal is happening. Marking the old map range unindexed happens before the actual deletion and happens undex indexLock. Marking the epoch either clean or dirty depending on whether the deletion is finished is again happening while the lock is being held.

Fixes #31700

[zsfelfoldi]

Replaced by #31708