Build(deps): Bump excon from 0.83.0 to 0.84.0 (#13664)

Bumps [excon](https://github.com/excon/excon) from 0.83.0 to 0.84.0.
- [Release notes](https://github.com/excon/excon/releases)
- [Changelog](https://github.com/excon/excon/blob/master/changelog.txt)
- [Commits](https://github.com/excon/excon/compare/v0.83.0...v0.84.0)

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

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Gemfile.lock

@@ -128,7 +128,7 @@ GEM
       sprockets (>= 3.3, < 4.1)
     ember-source (2.18.2)
     erubi (1.10.0)
-    excon (0.83.0)
+    excon (0.84.0)
     execjs (2.8.1)
     exifr (1.3.9)
     fabrication (2.22.0)