Correctly check http git access rights for reverse proxy authorized users

[lafriks]

Fixes reverse proxy authorized users for access rights to git repositories when accessing from git client.

Review changes with ?w=1 to easier see actual changes :)

[codecov-io]

Codecov Report

Merging #3721 into master will not change coverage.
The diff coverage is 11.11%.

@@           Coverage Diff           @@
##           master    #3721   +/-   ##
=======================================
  Coverage   35.76%   35.76%           
=======================================
  Files         289      289           
  Lines       41604    41604           
=======================================
  Hits        14879    14879           
- Misses      24527    24528    +1     
+ Partials     2198     2197    -1

Impacted Files	Coverage Δ
routers/repo/http.go	38.01% <11.11%> (ø)	⬆️
models/repo_indexer.go	48.3% <0%> (ø)	⬆️

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[mckaygerhard]

hi, this it's a fix or its only a compatibility feature? and when will going to be backported to 1.4 branch?

[lafriks]

@mckaygerhard it is bugfix and will be backported to 1.4 branch as soon other maintainers review&approve this PR

[mckaygerhard]

only one more.. lgtm