Update GitHub upload-artifact to v4 (#100)

v1 is deprecated and causes tests to fail

Author: davispuh

.github/workflows/ci.yml

@@ -36,7 +36,7 @@ jobs:
     - name: Run vulnerabilities check
       run: bundle exec rake audit
     - name: Upload simplecov results for coverage
-      uses: actions/upload-artifact@v1
+      uses: actions/upload-artifact@v4
       with:
         name: coverage
         path: coverage/
@@ -61,4 +61,4 @@ jobs:
         workingDirectory: ${{github.workspace}}
         debug: true
         coverageLocations: |
-          ${{github.workspace}}/coverage/coverage.json:simplecov
+          ${{github.workspace}}/coverage/coverage.json:simplecov