Replace behave framework with pytest-bdd and add DataSetComparator (#447)

* Replace behave with pytest_bdd

* Add value comparator

* Finish value compare

* Fix set compare

* Execute query and check result steps

* Make parser return bytes array rather than string

* Add NBA CSV data files

* Add types

* Generate insert stmt string

* Fix row comparing

* Generate create stmt string

* Use pytest-mproc's global scope to init nebula servers

* Fix compare bug

* Add student data

* Cleanup steps

* Fix parser bug

* Update parser

* Remove pytest-mproc

* Fix cleanup nebula services

* Fix ci test run parallel

* Replace conn pool creation with fixture

* Improve the free ports get function

* Fix workarround for class fixture usage

* improve free port find method

* Fix test spaces

* Change pytest temp base dir

* Improve kill nebula service logics

* Update workflow

* Fix github workflow step

* Address comments