bundle: Restore local install on macOS (#41482)

I just pulled and ran a local build via `script/bundle-mac -l -i` but
found that the resulting bundle wasn't installed as expected. (me:
"ToggleAllDocks!! Wait! Where is it?!") Looking into, it looks like the
`-l` flag was removed in #41392, leaving the `$local_only` var orphaned,
which then left the `-i/$local_install` flag unreachable. I suspect that
this was unintentional, so this PR re-adds the `-l/$local_only` flag to
`script/bundle-mac`.

I ran the build again and confirmed that local install seemed to work as
expected. (ie "ToggleAllDocks!! 🎉")

While here, I also removed the last reference to `$local_arch`, because
all other references to that were removed in #41392.

/cc @osiewicz 

Release Notes:

- N/A

---------

Co-authored-by: Conrad Irwin <conrad.irwin@gmail.com>

.github/workflows/run_tests.yml

@@ -46,7 +46,7 @@ jobs:
             echo "${output_name}=false" >> "$GITHUB_OUTPUT"
         }
 
-        check_pattern "run_action_checks" '^\.github/(workflows/|actions/|actionlint.yml)|tooling/xtask' -qP
+        check_pattern "run_action_checks" '^\.github/(workflows/|actions/|actionlint.yml)|tooling/xtask|script/' -qP
         check_pattern "run_docs" '^docs/' -qP
         check_pattern "run_licenses" '^(Cargo.lock|script/.*licenses)' -qP
         check_pattern "run_nix" '^(nix/|flake\.|Cargo\.|rust-toolchain.toml|\.cargo/config.toml)' -qP