Test/td 4376

* [TD-4382]<fix>: taosdemo query result file is null.

* modify CI
Co-authored-by: NShuduo Sang <sdsang@taosdata.com>
Co-authored-by: Nliuyq-617 <yqliu@taosdata.com>

[TD-3279]<fix>: memory link while perform delete action

commit 0c81e3c0ba89c86f6d17d51d5056146e177cace5
Author: Huo Linhe <linhehuo@gmail.com>
Date:   Fri May 14 10:27:13 2021 +0800

    [TD-4160]<fix>: remove python connector soft links, fix tests and documents

commit f439fce413423e7d7c97eef180c93d63dedab32e
Author: Huo Linhe <linhehuo@gmail.com>
Date:   Wed May 12 18:50:53 2021 +0800

    [TD-182]: bump python connector version to v2.0.10 (#6091)

    Also fix url error in setup.py

commit 4ae55d494a262e482f6b34e8bf193cc6af62a886
Author: Huo Linhe <linhehuo@gmail.com>
Date:   Wed May 12 09:49:26 2021 +0800

    [TD-4370]<fix>: merge python connector changes to master

    Inludes:

    [TD-182]<enhance>: use single repo for python connector (#6036)

    * [TD-182]<enhance>: use single repo for python connector

    Remove code for each platform and build up one single python code base
    for windows/osx/linux platforms and python2/python3 runtime.

    * [TD-182]<enhance>: remove redundant code in python connector

    * [TD-4149] <fix>: fix python connection config error

[TD-4355]<fix>

Fix/query

[td-4372]<fix>: fix the taosd server crash caused by dropping a child table, of which the indexed tag value is null.

Fix/query

Co-authored-by: NShuduo Sang <sdsang@taosdata.com>

TD-3279 TD-4328

[td-225] add log.

* [TD-3783]<fix>: taosdemo for windows generates rand string invalid.

* refactor disorder timestamp.

* refactor debug print.
Co-authored-by: NShuduo Sang <sdsang@taosdata.com>

[TD-4323]<fix>:  the deleted vnode does not need to commit, so as to …

[TD-4323]<fix>:  the deleted vnode does not need to commit, so as to speed up the deletion and avoid crash while balance

[td-4231]<enhance>: report error if only tags of the table are retrie…

[TD-4327]jenkins migration

* [TD-4296]<fix>: taosdemo sub keepProgress.

* make print sqlcount quiet.

* [TD-4296]<fix>: taosdemo subscribe keepprogress.

specified query topic thread safe.

* [TD-4296]<fix>: taosdemo subscribe keepProgress.

specified query thread safe.

* fix compile warning for mac.
Co-authored-by: NShuduo Sang <sdsang@taosdata.com>

* [TD-4322]<fix>: taosdemo query then fetch result.

* [TD-4322]<fix>: taosdemo fetch result.

check result file name length.
Co-authored-by: NShuduo Sang <sdsang@taosdata.com>

* [TD-4296]<fix>: taosdemo sub keepProgress.

* make print sqlcount quiet.
Co-authored-by: NShuduo Sang <sdsang@taosdata.com>

Enhancing crash_gen tool to report memory leaks in clustering mode

Co-authored-by: NShuduo Sang <sdsang@taosdata.com>

Co-authored-by: Nplum-lihui <huili@taosdata.com>