Handle path with whitespaces in build cmd

[callingmedic911]

Closes #11464.

• We could have either quoted the path so it's properly passed as an argument OR we don't use shell: true and let execa deal with it on its own. I went with the latter.
• I realized we probably don't need shell: true at other places in this file. (we probably don't need shell: true in other commands too, but trying not to creep up the scope of this PR)

[Josh-Walker-GM]

Looks good. CI is green and I tested locally on mac and windows and it worked well.

I can't recall why we had shell in all the various places we have. I'm sure there were good reasons for some but I bet some were just carried over without too much scrutiny.

[callingmedic911]

I think CI only runs the build without prerender and I made changes to the prerendering part. I still have to followup but Tobbe mentioned a possible case where it could fail https://redwoodjs.slack.com/archives/C03EHC69MFW/p1728584859571649?thread_ts=1728531967.903949&cid=C03EHC69MFW