Fix error message sanitiziation

[ethantkoenig]

Fixes two sanitization issues:

1. Previous usage of the HandleCloneUserCredentials function did not cover the case where a message contained a sensitive URLs multiple times; only the first usage would be sanitized.
2. In the MigratePost handler, an unsanitized error could reach the handleCreateError(..) function, which itself does not do any sanitization. As a result, unsanitized URL could be printed in logs.

This PR additionally:

• moves shared URL-sanitization code to modules/util
• does some refactoring to use net/url instead of manually parsing urls (Sanitize logs for mirror sync (#3057, #3082) #3078 (comment))

[codecov-io]

Codecov Report

Merging #3082 into master will decrease coverage by 0.01%.
The diff coverage is 0%.

@@            Coverage Diff             @@
##           master    #3082      +/-   ##
==========================================
- Coverage   33.26%   33.24%   -0.02%     
==========================================
  Files         272      273       +1     
  Lines       39939    39947       +8     
==========================================
- Hits        13284    13281       -3     
- Misses      24757    24767      +10     
- Partials     1898     1899       +1

Impacted Files	Coverage Δ
routers/repo/repo.go	21.81% <0%> (-0.16%)	⬇️
models/repo_mirror.go	3.46% <0%> (+0.25%)	⬆️
modules/util/sanitize.go	0% <0%> (ø)
routers/api/v1/repo/repo.go	32.99% <0%> (-0.09%)	⬇️
modules/process/manager.go	76.81% <0%> (-4.35%)	⬇️

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[lafriks]

LGTM

[sapk]

LGTM

[lafriks]

make LG-TM work

[lafriks]

@ethantkoenig please backport this also to #3078