Bump proxy-agent from 6.3.1 to 6.4.0

Bumps [proxy-agent](https://github.com/TooTallNate/proxy-agents/tree/HEAD/packages/proxy-agent) from 6.3.1 to 6.4.0.
- [Release notes](https://github.com/TooTallNate/proxy-agents/releases)
- [Changelog](https://github.com/TooTallNate/proxy-agents/blob/main/packages/proxy-agent/CHANGELOG.md)
- [Commits](https://github.com/TooTallNate/proxy-agents/commits/[email protected]/packages/proxy-agent)

---
updated-dependencies:
- dependency-name: proxy-agent
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

package.json

@@ -54,7 +54,7 @@
     "jsonminify": "^0.4.1",
     "lodash": "^4.17.21",
     "path-parse": "~1.0.7",
-    "proxy-agent": "6.3.1",
+    "proxy-agent": "6.4.0",
     "yargs": "17"
   },
   "devDependencies": {