Don't show awaiting approval header alert for already-approved projects

When the project creation workflow is finished, the following message is shown in the top alert bar:
`Your project is awaiting approval. Expect a decision in the next business day.`

However, even after the project is approved, if the project is edited and the user clicks the final 'Update Project' at the end of the workflow, they still see this message.

## Code Location
https://github.com/DemocracyLab/CivicTechExchange/blob/e0baf1768fc3ede735d9ccc969bb9d62a11c6e00/common/components/controllers/CreateProjectController.jsx#L183-L187