SERV-445: Update https-proxy-agent to ^3.0.0

[tylerlevine]

https://bitgoinc.atlassian.net/browse/SERV-445
Note: this only fixes the issue in CI, and lets us merge other PRs. A correct fix will require merging and releasing these changes in dependencies:

• Update https-proxy-agent to 3.0.0 XRPLF/xrpl.js#1054
• Update https-proxy-agent to fix a vulnerability TooTallNate/node-proxy-agent#47
• Update https-proxy-agent to fix a vulnerability TooTallNate/node-pac-proxy-agent#22

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (master@05d470e). Click here to learn what that means.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master     #560   +/-   ##
=========================================
  Coverage          ?   61.35%           
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  Files             ?       80           
  Lines             ?     8668           
  Branches          ?     1723           
=========================================
  Hits              ?     5318           
  Misses            ?     2600           
  Partials          ?      750

Flag	Coverage Δ
#integration	37.11% <ø> (?)
#unit	55.17% <ø> (?)

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[tylerlevine]

Had wrong ticket in commit message, rebased to fix