* build: update writing kafka example and document

* fixes kafka demo

* fix: refine wording

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Co-authored-by: Shuduo Sang <sangshuduo@gmail.com>

* build: add python demo to ci

* build: fix python demo

* build: add python demo to ci

* build: add fast write example to ci

* build: add kafka demo to ci

* fix kafka demo

* fix python demo

* fix python demo

* fix python demo

* fix python demo

* fix python demo

* test: add python test to 3.0 ci and run it

* ci: put taos.h in /usr/include directory

* fix: python test case

* fix: exit 0 with test success
Co-authored-by: Ntangfangzhi <fztang@taosdata.com>