Feature/dotnet popup (#10231)

* Add a pop up for dotnet install if not present

* Second option of default location for mac/linux

* correcting the pop up message

* remove extra dependency

* updating as per PR comments

extensions/sql-database-projects/package.json

@@ -26,6 +26,17 @@
     "Microsoft.mssql"
   ],
   "contributes": {
+    "configuration": [
+      {
+        "title": "%sqlDatabaseProjects.Settings%",
+        "properties": {
+          "sqlDatabaseProjects.netCoreSDKLocation": {
+            "type": "string",
+            "description": "%sqlDatabaseProjects.netCoreInstallLocation%"
+          }
+        }
+      }
+    ],
     "commands": [
       {
         "command": "sqlDatabaseProjects.new",