chore!(backend-shared): Remove deprecated npm proxy settings

[KSDaemon]

This PR removes deprecated proxy settings obtained from npm settings. So only common HTTP_PROXY and/or HTTPS_PROXY env vars are used.

This probably fixes #9723

[codecov]

Codecov Report

❌ Patch coverage is 0% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 49.15%. Comparing base (cb6dc3e) to head (b241f94).
⚠️ Report is 8 commits behind head on master.

Files with missing lines	Patch %	Lines
packages/cubejs-backend-shared/src/proxy.ts	0.00%	2 Missing ⚠️

❗ There is a different number of reports uploaded between BASE (cb6dc3e) and HEAD (b241f94). Click for more details.

HEAD has 1 upload less than BASE

Flag	BASE (cb6dc3e)	HEAD (b241f94)
cubesql	1	0

Additional details and impacted files

@@             Coverage Diff             @@
##           master    #9715       +/-   ##
===========================================
- Coverage   83.34%   49.15%   -34.20%     
===========================================
  Files         244      196       -48     
  Lines       74112    15947    -58165     
  Branches        0     3131     +3131     
===========================================
- Hits        61767     7838    -53929     
+ Misses      12345     7716     -4629     
- Partials        0      393      +393     

Flag	Coverage Δ
cube-backend	49.15% <0.00%> (?)
cubesql	?

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