Add Tag | Error validation message (20 char limit) should disappear when char count is ≤ 20

[dujes]

I'm submitting a...

• [x] Bug report
• [ ] Regression (a behavior that used to work and stopped working in a new release)
• [ ] Feature request
• [ ] Documentation issue or request

Context

Issue is reproducible while adding a new tag to any course.

Steps to Reproduce

1. Click on 'Add Tag' icon that is visible in the bottom-right corner of any course card in catalog
2. Enter > 20 chars in the input field ('Select a tag or add a new one')
3. Reduce char number to ≤ 20
4. Observe the error validation message

Expected Behavior

Validation message should disappear immediately when condition char ≤ 20 is satisfied.

Current Behavior

Error validation message (20 char limit) will remain visible below input field after reducing char number to ≤ 20.

Screenshots