Name length validation

[Inferato]

Description

According to the UserProfile limitation for the name field:
name = models.CharField(blank=True, max_length=255, db_index=True)
we need to add the validation for the name length.
A better solution would be to use the separate constant which we could use for both the model field and validation criteria, but considering that the field has been unchanged since Feb 2012 - it was rejected to simplify the fix.

Related: open-release/quince.master

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[mphilbrick211]

Hi @Inferato! Just flagging that there are a few failing checks. Would you mind taking a look?

[mphilbrick211]

Hi @openedx/2u-aperture! This is ready for review/merge.

[robrap]

@mphilbrick211: [inform] I am moving this on Contributions board from arch-bom to aperture.

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@Inferato 🎉 Your pull request was merged! Please take a moment to answer a two question survey so we can improve your experience in the future.

[edx-pipeline-bot]

2U Release Notice: This PR has been deployed to the edX staging environment in preparation for a release to production.

[edx-pipeline-bot]

2U Release Notice: This PR has been deployed to the edX production environment.