Issue reporter: Improve 'API rate limit' label

[aeschli]

• enter many search terms to the Issue reporter
• at some point 'API rate limit' shows up
• It wasn't clear to me what to do now

Ideally, this would never show up (not sure if it is feasible to use a hardcoded access token with limited capabilities)
Or, add a sentence that says that something like: 'Only 10 searches can be done within a minute'

[gregvanl]

I left this comment in the commit:
How about saying something like "GitHub query limit exceeded. Please wait."?
"API rate limit exceeded" does let the user know where the throttling occurred or what they should do.
Can the issue reporter retry the query automatically after a timeout?

[RMacfarlane]

How about this?

The time until reset is calculated from a value in GitHub's response. I can redo the search after the timeout. I'm not sure what token could be hardcoded safely, so will not attempt that right now.

[gregvanl]

I don't think you want to include specific numbers and timeout intervals since GitHub could change these. I would leave the message generic.

[RMacfarlane]

Ok, I'll just change it to "GitHub query limit exceeded. Please wait."