Fixed pip-compile --upgrade-package removes "via" annotation

[hramezani]

Fixes #929.

Changelog-friendly one-liner: Fixed pip-compile --upgrade-package removes "via" annotation.

Contributor checklist

• Provided the tests for the changes.
• Gave a clear one-line description in the PR (that the maintainers can add to CHANGELOG.md on release).
• Assign the PR to an existing or new milestone for the target version (following Semantic Versioning).

[atugushev]

Hello @hramezani,

Thanks for fixing this bug and the test! Could you use current PR template if the changes are user-facing, for it might need a changelog entry? Thanks!

[hramezani]

Hello @hramezani,

Thanks for fixing this bug and the test! Could you use current PR template if the changes are user-facing, for it might need a changelog entry? Thanks!

@atugushev Thanks for the comment. Description edited.

[codecov]

Codecov Report

Merging #931 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #931      +/-   ##
==========================================
+ Coverage   99.09%   99.09%   +<.01%     
==========================================
  Files          35       35              
  Lines        2321     2331      +10     
  Branches      300      301       +1     
==========================================
+ Hits         2300     2310      +10     
  Misses         13       13              
  Partials        8        8

Impacted Files	Coverage Δ
tests/test_cli_compile.py	100% <100%> (ø)	⬆️
piptools/scripts/compile.py	100% <100%> (ø)	⬆️

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[atugushev]

Great work! A few nit-pickings below 🤓

[atugushev]

Thanks for addressing to my request changes, i've marked all conversations as resolved!

[atugushev]

LGTM! 👍

[atugushev]

Thanks for your excellent work and your patience, @hramezani!