fix(versions): Handle missing versions folder

[provokateurin]

The catch references an potentially uninitialized variable and thus will fail if executed.

[provokateurin]

/backport to stable30

[provokateurin]

/backport to stable29

[provokateurin]

/backport to stable28

[backportbot]

The backport to stable28 failed. Please do this backport manually.

# Switch to the target branch and update it
git checkout stable28
git pull origin stable28

# Create the new backport branch
git checkout -b backport/3183/stable28

# Cherry pick the change from the commit sha1 of the change against the default branch
# This might cause conflicts, resolve them
git cherry-pick c61adfcb

# Push the cherry pick commit to the remote repository and open a pull request
git push origin backport/3183/stable28

Error: No changes found in backport branch

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Learn more about backports at https://docs.nextcloud.com/server/stable/go.php?to=developer-backports.

[provokateurin]

The method didn't exist back in stable28 yet, so backport failure is not a problem.