Try using the right syntax

Author: nickcharlton

.github/workflows/main.yml

@@ -80,15 +80,21 @@ jobs:
         with:
           cache: yarn
       - name: Install Ruby dependencies
-        run: BUNDLE_GEMFILE=gemfiles/${{ matrix.appraisal }}.gemfile bundle install
+        run: bundle install
+        env:
+          BUNDLE_GEMFILE: gemfiles/${{ matrix.appraisal }}.gemfile
       - name: Install JS dependencies
         run: yarn install
       - name: Setup the environment
         run: cp .sample.env .env
       - run: cp spec/example_app/config/database.yml.sample spec/example_app/config/database.yml
       - name: Setup the database
-        run: BUNDLE_GEMFILE=gemfiles/${{ matrix.appraisal }}.gemfile bundle exec rake db:setup
+        run: bundle exec rake db:setup
+        env:
+          BUNDLE_GEMFILE: gemfiles/${{ matrix.appraisal }}.gemfile
       - name: Build assets
         run: yarn run build && yarn run build:css
       - name: Run tests
-        run: BUNDLE_GEMFILE=gemfiles/${{ matrix.appraisal }}.gemfile bundle exec rspec
+        run: bundle exec rspec
+        env:
+          BUNDLE_GEMFILE: gemfiles/${{ matrix.appraisal }}.gemfile