Add support for Bitbucket Data Center webhooks (#14674)

Add support for receiving webhooks from Bitbucket Data Center, and add support for posting build statuses back

Note that this is very explicitly only for Bitbucket Data Center.
The entire webhook format and API is entirely different for Bitbucket Cloud.

awx/ui/src/screens/Template/shared/WebhookSubForm.js

@@ -112,6 +112,12 @@ function WebhookSubForm({ templateType }) {
       label: t`GitLab`,
       isDisabled: false,
     },
+    {
+      value: 'bitbucket_dc',
+      key: 'bitbucket_dc',
+      label: t`Bitbucket Data Center`,
+      isDisabled: false,
+    },
   ];
 
   if (error || webhookKeyError) {