drop keeper + add idle sessions gc

Author: asmyasnikov

CHANGELOG.md

@@ -1,3 +1,6 @@
+* Replaced internal table client background worker to plain wait group for control spawned goroutines
+* Replaced internal table client background session keeper to internal background session garbage collector for idle sessions
+
 ## v3.34.2
 * Added some description to error message from table pool get
 * Moved implementation `sugar.GenerateDeclareSection` to `internal/table`