Automatically disable language service when non T-SQL sql language is detected (#2438)

* langauge service switch start

* T sql detection function done

* updated count

* make it case insensitive

* more updates

* removed extra function

* finished language service switch

* added tests and removed some common object name keywords

* added tests; they got left out of my last commit

* organized keyword list

* trimmed down words list

* moved tests to correct file, and made tests cleaner

* added one more test case

* addressed pr commens

* trimmed word list down

* do not check identifiers for non sql text

* added tests

* fixed pr comments

* cfixed imports

* separated file path test and regular tests

* updated tests

* clened up tests

* added cs proj file

* pr comment

Author: laurennat