[orc8r] Copy labels explicitly to avoid rare overwriting in metric conversion to gauges

[Scott8440]

Signed-off-by: Scott8440 scott8440@gmail.com

Summary

I'll be honest I really don't know why this is necessary.

• While testing getting new stats from AGWs, I noticed summaries from the AGW were only coming through with the {quantile="1"} metric (while there were 4 other quantiles)
• It seemed like a pretty clear issue of pointers being overwritten in a loop in gaugeconverter.go, although I still don't really know how that was happening
• What's even weirder is that this was only happening on metrics from the AGW, and there were quite a few summaries that originated in the cloud where this error never occurred (basically identical metrics too)
• EVEN weirder is that I cannot replicate this in tests
• I fixed the problem by just messing around until something worked and now it works so I give up trying to understand

Test Plan

• Test by pushing a summary through the pipeline, all expected labels show up.
• No other metrics were affected
  

[xjtian]

with changes