chore(docs): Update .repo-metadata.json for backupdr

[dandhlee]

Updating the repo.metadata.json for documentation path: https://cloud.google.com/python/docs/reference/backupdr/latest

The current link doesn't work.

Please let me know if this can be manually fixed or if it needs to be updated from the serviceconfigs.

[parthea]

Can we keep the current docs link and change the name to google-cloud-backupdr instead? This is what we had in the initial commit. 1e9fb9d

Change

"name": "backupdr",

to

"name": "google-cloud-backupdr",

cc @ohmayr