Fix metrics auth token detection

[barkap]

Metrics token authorization currently does not work with token and metrics enabled in config. There's always 401 response without any data. This fixes header detection.

[techknowlogick]

Thanks for PR @barkap, would you be able to add a test for this?

[codecov-io]

Codecov Report

Merging #6006 into master will not change coverage.
The diff coverage is 0%.

@@           Coverage Diff           @@
##           master    #6006   +/-   ##
=======================================
  Coverage   38.72%   38.72%           
=======================================
  Files         332      332           
  Lines       48992    48992           
=======================================
  Hits        18973    18973           
  Misses      27271    27271           
  Partials     2748     2748

Impacted Files	Coverage Δ
routers/metrics.go	0% <0%> (ø)	⬆️

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[barkap]

Thanks for PR @barkap, would you be able to add a test for this?

I'm not too familiar with gitea as a whole and existing go tests mostly fail for me so I'm probably unable to write new test with mocks for this package at the time.

[techknowlogick]

@barkap that's ok, thanks for explaining. My computer is so low powered that I rely on drone for running my tests as otherwise it'd be >1.5hours just to test against sqlite 😢 maybe it is time for me to get a new computer 🤔

Would you be able to send a backport of this PR against the release/v1.7 branch? If you need any clarification or assistance please let me know and I can help you out.

[barkap]

Yes, I'll send pr in a bit. Thank you.