When enabling an S3 remote with hybrid encryption, I get a file locking error:
```
$ git annex enableremote s3remote
git-annex: .git/annex/creds/__S3_REMOTE_UUID_REDACTED__: openFile: resource busy (file is locked)
```
I can confirm that this happens when no previous process is running (and lsof shows nothing open before running enableremote), for example in the motivating case here of cloning to a new, freshly-mounted HDD.
If I copy the `.git/annex/creds/__S3_REMOTE_UUID_REDACTED__` file from an existing clone of the repository to this new one, then enableremote works fine.
```
$ git annex enableremote s3remote
enableremote s3remote (encryption update) (to gpg keys: HEXREDACTED) ok
(recording state in git...)
```
### What steps will reproduce the problem?
For me, with a source a repository that has a pre-configured S3 special remote: