Bug 1620860 - mozlint/yamllint - Fix the python path include r=Dexter

Differential Revision: https://phabricator.services.mozilla.com/D65908

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

tools/lint/yamllint_/__init__.py

@@ -63,7 +63,7 @@ def get_yamllint_binary(mc_root):
 
     # yamllint is vendored in mozilla-central: let's use this
     # if no environment variable is found.
-    return os.path.join(mc_root, 'third_party', 'python', 'yamllint')
+    return os.path.join(mc_root, 'third_party', 'python', 'yamllint', 'yamllint')
 
 
 def _run_pip(*args):