Do not show an error when polling notes fails

What does this MR do and why?

Issue: #381431

When a user is on the Issue or Merge Request page, we poll for new notes for the issuable. When the request fails for two times, we show an error.

While we technically remove the error again once the user has a connection again, I'd argue we should not show it in the first place as the user never initiated an action.

With this MR we remove the error message.

Screenshots or screen recordings

Before	After
before_1080	after_1080

How to set up and validate locally

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