Bump octicons_helper from 19.7.0 to 19.8.0

Bumps [octicons_helper](https://github.com/primer/octicons) from 19.7.0 to 19.8.0.
- [Release notes](https://github.com/primer/octicons/releases)
- [Changelog](https://github.com/primer/octicons/blob/main/CHANGELOG.md)
- [Commits](primer/octicons@v19.7.0...v19.8.0)

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

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

Gemfile.lock

@@ -233,10 +233,10 @@ GEM
       rack (>= 1.2, < 4)
       snaky_hash (~> 2.0)
       version_gem (~> 1.1)
-    octicons (19.7.0)
-    octicons_helper (19.7.0)
+    octicons (19.8.0)
+    octicons_helper (19.8.0)
       actionview
-      octicons (= 19.7.0)
+      octicons (= 19.8.0)
       railties
     octokit (7.1.0)
       faraday (>= 1, < 3)