[CP] 🔥 Do not format the messages file for gen-l10n (#119596)

[AlexV525]

(cherry picked from commit 4ae2d3b)

The stable branch does not have #115502 so the change is slightly different from the original.

The request might be held until #119679 has landed.

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[godofredoc]

@AlexV525 can you please help us with a rebase?

[thkim1011]

Closing as the consensus was that there's currently a workaround to this issue by disabling the format flag, so we should rather wait for this to land in the next release. cc @christopherfujino