* restore .gitmodules

* Revert "[TD-13408]<test>: move tests directory out"

This reverts commit 7db7bd9337cedc4cd0e3f3b16618b97d09791eaa.

* revert to make tests back

* immigrate file change in stand-alone repo to TDengine

* remove tests repository checkout
Co-authored-by: Ntangfangzhi <fztang@taosdata.com>

* [TD-13408]<test>: move tests directory out

* restore Jenkinsfile due to tests dir removal

* add --remote parameter to git submodule update

* git reset hard before checkout to branch

* call git submodule update for some submodules

* remove tests directory before checkout due to conflict

* as all branches remove tests, no need to remove it in script
Co-authored-by: Ntangfangzhi <fztang@taosdata.com>

[TD-11861]<test>: modify testcase that it will exit without continuing execution when json files have been checked unsuccessfully

[TD-10551]<test>: add taosdemo testcase that it provides define timestamp column with stmt in sample.csv

* [TD-5872]<fix>: taosdemo stmt improve.

* refactor stmt functions.

* [TD-5872]<fix>: taosdemo stmt csv perf improve.

* rand func back to early impl.

* fix windows/mac compile error.

* fix empty tag sample.

* [TD-5873]<test>add stmt’performance taosdemo testcase
Co-authored-by: NShuduo Sang <sdsang@taosdata.com>
Co-authored-by: tomchon <haoran920c@163.com>