test: add tag index basic function verify case

fix: taosd crash issue caused of out of fd 

fix(tsdb/cache): use state's tsdb instead of readers

feat(query): optimize percentile function performance

fix: dead lock while create transaction on same db or stable

feat:stream coverity scan

fix: fix issues reported by coverity scan

fix: coverity scan problem

fix: create stream semantic check

ci: install defined version python connector

This reverts commit f7a8393c.