fix(share): use user timezone to parse share expiration date

[Altahrim]

• Resolves: [Bug]: Issue with forced share expiration in the mornings here in New Zealand #38405
• Resolves: [Bug]: Use system timezone in calculation of share times #42453

Summary

If an user in UTC+1 try to create a share at 00:00, it's day D for him, but D-1 for the server (UTC).
This fix aims to apply the correct offset.

Later, it will be better to also handle hours for share expiration.

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)

[Altahrim]

/backport to stable28

[Altahrim]

/backport to stable27

[Altahrim]

/backport to stable26

[skjnldsv]

/skjnldsv-backport to stable26

[skjnldsv]

/skjnldsv-backport to stable27

[backportbot]

The backport to stable26 failed. Please do this backport manually.

# Switch to the target branch and update it
git checkout stable26
git pull origin stable26

# Create the new backport branch
git checkout -b backport/42660/stable26

# Cherry pick the change from the commit sha1 of the change against the default branch
# This might cause conflicts, resolve them
git cherry-pick cc3a2c351a2db4c30a2f0dc1bde73ba024e88602

# Push the cherry pick commit to the remote repository and open a pull request
git push origin backport/42660/stable26

Error: Validation Failed: {"resource":"PullRequest","code":"custom","message":"No commits between stable26 and backport/42660/stable26"}

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