This bug occurred when the same xDS server was configured twice in the
same bootstrap config, once in an authority and again as the top-level
server. In that case, we were incorrectly failing to de-dup them and
were creating a separate channel for the LRS stream than the one that
already existed for the ADS stream. We fix this by canonicalizing the
server keys the same way in both cases.
As a separate follow-up item, I will work on trying to find a better way
to key these maps that does not suffer from this kind of fragility.
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