Support passing more than one GITHUB_TOKEN #551
Description
At my org, we use several different bot accounts for different workflows. In order to use the exporter now, I can only pass one token at a time which means I have to run N exporters in order to obtain rate limit information about my N tokens.
I believe it would be better, resource-wise, to have a single exporter running, and that exporter iterates through a list of tokens, recording the rate limit metrics for each one of them.