Fix search path for relative paths in roles (fixes #17877)

(cherry picked from commit 72f0aaf606)

lib/ansible/parsing/dataloader.py

@@ -312,6 +312,10 @@ class DataLoader():
                     if b_mydir.endswith(b'tasks'):
                         search.append(os.path.join(os.path.dirname(b_mydir), b_dirname, b_source))
                         search.append(os.path.join(b_mydir, b_source))
+                    else:
+                        # don't add dirname if user already is using it in source
+                        if b_source.split(b'/')[0] == b_dirname:
+                            search.append(os.path.join(b_upath, b_source))
                         else:
                             search.append(os.path.join(b_upath, b_dirname, b_source))
                         search.append(os.path.join(b_upath, b'tasks', b_source))