The `/unsubscribe` quick action doesn't update the page to make `/subscribe` available

Steps to reproduce.

Setup:

1. Open an issue or MR that your're subscribed to
2. Write /unsubscribe in comments section and submit the commit.
3. A blue label with "Your commands have been executed" appears.

Check 1:

1. Write /s in comment section.
2. A dropdown list should open with /subscribe option available and, optionally, highlighted.

Right now /subscribe is not available, but /unsubscribe is offered and forced with autocompletion. Although it's possible to write /subscribe, close the dropdown list and submit.

Check 2:

1. The subscription button on the right should have updated text: "Subscribe"

Now the button says "Unsibscribe" as if the subscription status haven't changed.

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Same problem with using /subscribe where you weren't.