Fix project name validation

[maximlt]

To allow project names like census2020.

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[maximlt]

@Azaya89 this should allow you to name the new project census2020. Feel free to open PRs like that in the future to update dodo.py or other files in the repo!

[Azaya89]

@Azaya89 this should allow you to name the new project census2020. Feel free to open PRs like that in the future to update dodo.py or other files in the repo!

Thank you. I'm still in favor of renaming the first one to census2010 though.