test: add keep expired cases

fix(all): fixed coverity scan problems for second submiting

enh: insert parser refactor

avoid invalid read/write

fix(sync): add error log when pState is NULL

refactor: reduce the buffered blocks in sink node.

fix(query): refactor and fix some coverity issues.

Revert "test: build taosx and add test case of taosx"

fix(stream): stream state invalid cur

fix(query): remove redundant ts cols in cache scan.

test: build taosx and add test case of taosx

doc: add explanation for dropped 2.x configuration variables