Do not output modScript include result w/o explicit string return

Addresses #11705
Ignore output only if result is boolean

Adjustments to further address #11705
Add explicit return to all modScript includes
Merge remote-tracking branch 'upstream/pr/11755' into pr/11755

* upstream/pr/11755:
  Add explicit return to all modScript includes
  Ignore output only if result is boolean
  Do not output modScript include result w/o explicit string return

Conflicts:
	core/docs/changelog.txt