fix(win-msi): add bin to PATH per-machine after installation (#29099)

#22856 made it possible for the msi installer to perform per-user
installations, which caused problems for users that already had
per-machine installations trying to update (the Windows Installer does
not support major upgrades across installation context, see #22933 and
https://stackoverflow.com/a/15498911). It was then reverted in #22949,
but the scope of the modification to the PATH environment variable was
not reverted.

(cherry picked from commit a18652ed61)

cmake.packaging/WixPatch.xml

@@ -6,7 +6,7 @@
       Name='PATH'
       Action='set'
       Permanent='no'
-      System='no'
+      System='yes'
       Part='last'
       Value='[INSTALL_ROOT]bin'
     />