test: don't reset workspace when running E2E tests (#7122)

The E2E test script unexpectedly runs a `git checkout .` on the CLI
repository. If you run it locally and have any uncommitted changes,
oops! It just discarded your work.

#7119 removes the
`package.json#scripts` pre-publish mangling that we used to do, which
is ostensibly why we needed this in the first place.

Author: ndhoule

tools/e2e/setup.js

@@ -134,8 +134,6 @@ export const setup = async () => {
       cwd: rootDir,
     })
 
-    // Reset the workspace, as npm publish does patch package.json etc
-    await execa('git', ['checkout', '.'], { cwd: rootDir })
     await execa('npm', ['install', '--no-audit'], { cwd: rootDir })
 
     console.log(`------------------------------------------