Improve identifier mapping logic for Bitbucket Server integration

Author: dennis-bilson-port

docs/build-your-software-catalog/sync-data-to-catalog/git/bitbucket/bitbucket-server/bitbucket-server.md

@@ -779,7 +779,7 @@ resources:
     port:
       entity:
         mappings:
-          identifier: .id | tostring
+          identifier: (.toRef.repository.slug // .toRef.repository.project.key) + "-" + (.id|tostring)
           title: .title
           blueprint: '"bitbucketPullRequest"'
           properties: