Adjust message in timezone conflict form

Summary:
This applies a suggestion initially proposed in
https://we.phorge.it/D25420#12264

Test Plan:

• Change your browser/system timezone to differ from your Phorge profile timezone
• Click the notice that Phorge shows at the bottom left about the timezone mismatch
• Confirm that the form text has been changed as per the diff in this revision

Reviewers: O1 Blessed Committers, valerio.bozzolan

Reviewed By: O1 Blessed Committers, valerio.bozzolan

Subscribers: aklapper, tobiaswiese, valerio.bozzolan, Matthew, Cigaryno

Differential Revision: https://we.phorge.it/D25458