This 'Custom Study' screen is superfluous:

Good First Issue!

• Relevant classes: TagLimitFragment.kt; CustomStudyDialog.kt
• Either
  • If there are no tags, change the text (sentence_choose_tags) in CustomStudyDialog and skip the tag selection screen
    • define an extension method fun Tags.count() by counting the result of Tags.all()
  • OR suggest another appropriate UX