Make test_run_string pass when the default shell is not bash (#137)

Author: adamtheturtle

test/test_unit.py

@@ -10,7 +10,7 @@
 
 def test_run_string() -> None:
     """Validate run() called with a single string command."""
-    cmd = "echo 111 && >&2 echo 222"
+    cmd = 'bash -c "echo 111 && >&2 echo 222"'
     old_result = subprocess.run(
         cmd,
         shell=True,