hooks/format: call mach with python3 directly instead of through …

…`sh` (Bug 1749681) r=firefox-build-system-reviewers,glandium

Previously `mach` was both valid shell and valid Python. After all the recent
`mach` work, the need to have `mach` run as a shell script is gone and the
hack has been removed, leaving `mach` as a pure-Python script. Nice!

We took advantage of this hack when running the commit hook extensions
on Windows, though I can't remember exactly why. In any case we can move
to calling `mach` via `python3` directly instead of passing through `sh`.

Differential Revision: https://phabricator.services.mozilla.com/D135751

--HG--
extra : moz-landing-system : lando

hgext/clang-format/__init__.py

@@ -54,7 +54,7 @@ def call_clang_format(repo, changed_files):
     mach_path = os.path.join(repo.root, b'mach')
     arguments = [b'clang-format', b'-p'] + path_list
     if os.name == 'nt':
-        clang_format_cmd = [b'sh', b'mach'] + arguments
+        clang_format_cmd = [b'python3', b'mach'] + arguments
     else:
         clang_format_cmd = [mach_path] + arguments
     subprocess.call(clang_format_cmd)

hgext/js-format/__init__.py

@@ -49,7 +49,7 @@ def call_js_format(repo, changed_files):
     mach_path = os.path.join(repo.root, b'mach')
     arguments = [b'eslint', b'--fix'] + path_list
     if os.name == 'nt':
-        js_format_cmd = [b'sh', b'mach'] + arguments
+        js_format_cmd = [b'python3', b'mach'] + arguments
     else:
         js_format_cmd = [mach_path] + arguments
     subprocess.call(js_format_cmd)