AO3-6867 Increase tag name limit to 150

[brianjaustin]

Pull Request Checklist

• Have you read "How to write the perfect pull request"?
• Have you read the contributing guidelines?
• Have you added tests for any changed functionality?
• Have you added the Jira issue number
  as the first thing in your pull request title (e.g. AO3-1234 Fix thing)
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Issue

https://otwarchive.atlassian.net/browse/AO3-6867

Purpose

Update the tag name limit from 100 to 150 characters, per TW.