Improve the fork message in the UI

The previous message about pipelines in forks did not work well for
our users. This change is an attempt to improve it to make clearer
what the situation is, and what users need to do.

app/assets/javascripts/vue_merge_request_widget/mr_widget_options.vue

@@ -514,7 +514,7 @@ export default {
           >
             {{
               s__(
-                'mrWidget|Fork merge requests do not create merge request pipelines which validate a post merge result',
+                'mrWidget|If the last pipeline ran in the fork project, it may be inaccurate. Before merge, we advise running a pipeline in this project.',
               )
             }}
           </mr-widget-alert-message>

locale/gitlab.pot

@@ -36988,15 +36988,15 @@ msgstr ""
 msgid "mrWidget|Fast-forward merge is not possible. To merge this request, first rebase locally."
 msgstr ""
 
-msgid "mrWidget|Fork merge requests do not create merge request pipelines which validate a post merge result"
-msgstr ""
-
 msgid "mrWidget|Fork project merge requests do not create merge request pipelines that validate a post merge result unless invoked by a project member."
 msgstr ""
 
 msgid "mrWidget|If the %{missingBranchName} branch exists in your local repository, you can merge this merge request manually using the command line"
 msgstr ""
 
+msgid "mrWidget|If the last pipeline ran in the fork project, it may be inaccurate. Before merge, we advise running a pipeline in this project."
+msgstr ""
+
 msgid "mrWidget|Jump to first unresolved thread"
 msgstr ""