chore: bump pac-resolver to 4.2.0 (aws#13914)

This in turn bumps `netmask`. 

See TooTallNate/node-pac-resolver#25

----

*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

package.json

@@ -25,10 +25,8 @@
     "standard-version": "^9.1.1",
     "typescript": "~3.9.9"
   },
-  "netmask-resolutions-comment": "transitive dep from [email protected]. review when dependencies upgrade",
   "tap-mocha-reporter-resolutions-comment": "should be removed or reviewed when nodeunit dependency is dropped or adjusted",
   "resolutions": {
-    "netmask": "2.0.1",
     "tap-mocha-reporter": "^5.0.1"
   },
   "repository": {

yarn.lock

@@ -6964,7 +6964,7 @@ nested-error-stacks@^2.0.0:
   resolved "https://registry.yarnpkg.com/nested-error-stacks/-/nested-error-stacks-2.1.0.tgz#0fbdcf3e13fe4994781280524f8b96b0cdff9c61"
   integrity sha512-AO81vsIO1k1sM4Zrd6Hu7regmJN1NSiAja10gc4bX3F0wd+9rQmcuHQaHVQCYIEC8iFXnE+mavh23GOt7wBgug==
 
-[email protected], netmask@^1.0.6:
+netmask@^2.0.1:
   version "2.0.1"
   resolved "https://registry.yarnpkg.com/netmask/-/netmask-2.0.1.tgz#5a5cbdcbb7b6de650870e15e83d3e9553a414cf4"
   integrity sha512-gB8eG6ubxz67c7O2gaGiyWdRUIbH61q7anjgueDqCC9kvIs/b4CTtCMaQKeJbv1/Y7FT19I4zKwYmjnjInRQsg==