Alanren/integration test (#3657)

* add an extension for integration tests

* setup ads before running test

* test setup

* test cases

* bash script

* shorter temp folder name

* code cleanup

* add commented out original code

* fix test error

* test result path

* rename results file

* change file path

* report smoke test results

* test stablize

* test stablization and configurable test servers

* fix smoke test error

* connection provider

* simplify the integration test script

* add comment

* fix tslint error

* address PR comments

* add temp log to check whether the environment variable is already set

* remove temp log

* move api definition to testapi typing file

* exclude integration tests extension

* address comments

build/gulpfile.vscode.js

@@ -65,6 +65,8 @@ const excludedExtensions = [
 	'vscode-colorize-tests',
 	'ms-vscode.node-debug',
 	'ms-vscode.node-debug2',
+	// {{SQL CARBON EDIT}}
+	'integration-tests',
 ];
 
 // {{SQL CARBON EDIT}}