Exclude projects dropdown from revert modal

What does this MR do?

We use the same form component for cherry-pick and revert features.

In !55970 (merged) we added a projects dropdown to the shared form but the projects dropdown should only display on the cherry-pick modal.

Screenshots (strongly suggested)

before	after

Does this MR meet the acceptance criteria?

Conformity

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Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers