Description
From Slack

• exact_length in traditional rules passes int values
• but exact_length in strict rules passes only string values
• it is not intuitive that the rule ‘required|numeric|exact_length[10] is invalid, and if you pass 1234567890, you will get the error "The XXX field must be exactly 10 characters in length."

Checklist:

• Securely signed commits
• Component(s) with PHPDoc blocks, only if necessary or adds value
• Unit testing, with >80% coverage
• User guide updated
• Conforms to style guide