revert workaround yarn commands since they operate on compiled repo

Author: lukekarrys

tasks/e2e-installs.sh

@@ -173,8 +173,8 @@ CI=true npm test
 echo yes | npm run eject
 
 # Temporary workaround for https://github.com/facebook/create-react-app/issues/6099
-rm package-lock.json
-npm install @babel/plugin-transform-react-jsx-source @babel/plugin-syntax-jsx @babel/plugin-transform-react-jsx @babel/plugin-transform-react-jsx-self
+rm yarn.lock
+yarn add @babel/plugin-transform-react-jsx-source @babel/plugin-syntax-jsx @babel/plugin-transform-react-jsx @babel/plugin-transform-react-jsx-self
 
 # Ensure env file still exists
 exists src/react-app-env.d.ts

tasks/e2e-kitchensink-eject.sh

@@ -121,8 +121,8 @@ npm link "$temp_module_path/node_modules/test-integrity"
 echo yes | npm run eject
 
 # Temporary workaround for https://github.com/facebook/create-react-app/issues/6099
-rm package-lock.json
-npm install @babel/plugin-transform-react-jsx-source @babel/plugin-syntax-jsx @babel/plugin-transform-react-jsx @babel/plugin-transform-react-jsx-self
+rm yarn.lock
+yarn add @babel/plugin-transform-react-jsx-source @babel/plugin-syntax-jsx @babel/plugin-transform-react-jsx @babel/plugin-transform-react-jsx-self
 
 # Link to test module
 npm link "$temp_module_path/node_modules/test-integrity"