Fix bound address/port for caddy's certmagic library

[bminer]

This is my attempt to fix issue created by d2ea21d when switching to Caddy's certmagic library. I believe that the call to ManageSync causes Gitea to try and listen on port 80 even if PortToRedirect is set.

Please test this fix, but I think it works. Thoughts?

[codecov-commenter]

Codecov Report

Merging #15758 (9e1208e) into main (114c85e) will decrease coverage by 0.00%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##             main   #15758      +/-   ##
==========================================
- Coverage   43.93%   43.93%   -0.01%     
==========================================
  Files         678      678              
  Lines       81945    81950       +5     
==========================================
- Hits        36005    36004       -1     
- Misses      40069    40075       +6     
  Partials     5871     5871              

Impacted Files	Coverage Δ
cmd/web_letsencrypt.go	0.00% <0.00%> (ø)
modules/process/manager.go	72.83% <0.00%> (-2.47%)	⬇️
models/repo_list.go	77.04% <0.00%> (-0.78%)	⬇️
modules/util/timer.go	85.71% <0.00%> (+42.85%)	⬆️

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[zeripath]

the thing is certmagic shouldn't be opening any ports itself. We open and control these ports ourselves.

[6543]

as per zeripath, we should find out why certmagic would (if ..) open a port itself and consider it a bug

[zeripath]

the ListenHost and AltHTTPPort are used in the challenge solvers - that's why they're needed

outofdate

[zeripath]

make lgtm work