Code review comment for ~lgp171188/lp-source-dependencies:update-dohq-artifactory-version-fix

You shouldn't delete the old file. In general, merges to lp-source-dependencies should either add files or delete them, not both; deletions should only happen after all environments have been upgraded to not use the old file any more (and aren't in any way urgent, so we usually only delete files in bulk and infrequently).