Move all static validations to the setup job

The default rake task is release_checks. This runs `lint`, `validate`
prior to `parallel_spec` and ends with the `check` task. These static
tasks shouldn't differ for the matrix job and can be run prior to
running the whole test suite. Then in the actual test matrix, it only
needs to run the tests (in parallel). This saves some CI resources when
a static check fails.

Author: ekohl

moduleroot/.github/workflows/ci.yml.erb

@@ -20,8 +20,8 @@ jobs:
         with:
           ruby-version: '2.7'
           bundler-cache: true
-      - name: Run rake validate
-        run: bundle exec rake validate
+      - name: Run static validations
+        run: bundle exec rake validate lint check
       - name: Run rake rubocop
         run: bundle exec rake rubocop
       - name: Setup Test Matrix
@@ -48,7 +48,7 @@ jobs:
           ruby-version: ${{ matrix.ruby }}
           bundler-cache: true
       - name: Run tests
-        run: bundle exec rake
+        run: bundle exec rake parallel_spec
 <%- if Dir[File.join(@metadata[:workdir], 'spec', 'acceptance', '**', '*_spec.rb')].any? -%>
 
   acceptance: