Remove remind button when in a closed group

Summary

Remind button shows in a closed group.

Steps to reproduce

1. Go to a closed group
2. Hit remind

Platform information

Cross-platform suspected replicated Ubuntu 19.04 / Chromium

What is the current bug behavior?

User seemingly has the option to remind.

What is the expected correct behavior?

User should not have the option to remind.

Relevant logs and/or screenshots

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Possible fixes

(If you can, link to the line of code that might be responsible for the problem)