change zsh tests to not use docker

Author: DannyBen

.github/workflows/test.yml

@@ -22,8 +22,5 @@ jobs:
         ruby-version: '${{ matrix.ruby }}'
         bundler-cache: true
 
-    - name: Setup tmate session
-      uses: mxschmitt/action-tmate@v3
-
     - name: Run tests
       run: bundle exec rspec

spec/completely/zsh_spec.rb

@@ -13,7 +13,9 @@
   end
 
   subject do
-    `docker run --rm -it -v $PWD/spec/tmp:/app dannyben/zsh #{shell} /app/test.sh`.strip
+    Dir.chdir 'spec/tmp' do
+      `#{shell} test.sh`.strip
+    end
   end
 
   describe "completions script and test script" do