chore(deps): update dependency ruby to v2.7.8 (#500)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [ruby](https://www.ruby-lang.org)
([source](https://redirect.github.com/ruby/ruby)) | uses-with | patch |
`2.7.3` -> `2.7.8` |

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.github/workflows/ci.yml

@@ -29,7 +29,7 @@ jobs:
       - name: Install Ruby
         uses: ruby/setup-ruby@v1
         with:
-          ruby-version: 2.7.3
+          ruby-version: 2.7.8
 
       - name: Install Dependencies
         run: npm install