Bug/auto complete pr ado 2019 (#309)

* Added new inputs for docker image source

* Added new variabels to `getSharedVariables.ts`
Changed task to use string for simplication instead of connected service

* Modified task to use new input variables for docker image registry + repository

* Resolving #288 by bumping PR API version to the previous version

Co-authored-by: Patrick Bigler <patrick.bigler@ideaintegrations.com>

src/script/azure_helpers.rb

@@ -74,7 +74,7 @@ def pull_request_auto_complete(pull_request_id, auto_complete_user_id, merge_str
                 response = patch(source.api_endpoint +
                     source.organization + "/" + source.project +
                     "/_apis/git/repositories/" + source.unscoped_repo +
-                    "/pullrequests/#{pull_request_id}?api-version=6.0", content.to_json)
+                    "/pullrequests/#{pull_request_id}?api-version=5.0", content.to_json)
             end
 
             def pull_request_approve(pull_request_id, reviewer_email, reviewer_token)