Fix several regressions in master (#613)

* Fix service option type enum

* Fix broken Explain button and Actual plan command

src/sql/workbench/api/common/sqlExtHostTypes.ts

@@ -15,17 +15,6 @@ export enum ServiceOptionType {
 	object = 6
 }
 
-// SQL added extension host types
-export enum ServiceOptionTypeNames {
-	string = 'string',
-	multistring = 'multistring',
-	password = 'password',
-	number = 'number',
-	category = 'category',
-	boolean = 'boolean',
-	object = 'object'
-}
-
 export enum ConnectionOptionSpecialType {
 	serverName = 'serverName',
 	databaseName = 'databaseName',