fix(docs): Fix dead documentation link for Windows file names

[nickvergessen]

Before: https://docs.nextcloud.com/server/33/go.php?to=
After: https://docs.nextcloud.com/server/33/go.php?to=admin-windows-compatible-filenames

Checklist

• Code is properly formatted
• Sign-off message is added to all commits
• Tests (unit, integration, api and/or acceptance) are included
• Screenshots before/after for front-end changes
• Documentation (manuals or wiki) has been updated or is not required
• Backports requested where applicable (ex: critical bugfixes)
• Labels added where applicable (ex: bug/enhancement, 3. to review, feature component)
• Milestone added for target branch/version (ex: 32.x for stable32)

[nickvergessen]

/backport to stable33

[nickvergessen]

/backport to stable32

[nickvergessen]

/backport to stable31

[backportbot]

The backport to stable31 failed. Please do this backport manually.

# Switch to the target branch and update it
git checkout stable31
git pull origin stable31

# Create the new backport branch
git checkout -b backport/58289/stable31

# Cherry pick the change from the commit sha1 of the change against the default branch
# This might cause conflicts, resolve them
git cherry-pick bb1b12b2

# Push the cherry pick commit to the remote repository and open a pull request
git push origin backport/58289/stable31

Error: Failed to check for changes with origin/stable31: 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.