Don't say Git.execute uses a shell, in its summary

The top line of the Git.execute docstring said that it used a
shell, which is not necessarily the case (and is not usually the
case, since the default is not to use one). This removes that
claim while keeping the top-line wording otherwise the same.

It also rephrases the description of the command parameter, in a
way that does not change its meaning but reflects the more common
practice of passing a sequence of arguments (since portable calls
that do not use a shell must do that).

Author: EliahKagan

git/cmd.py

@@ -842,12 +842,12 @@ def execute(
         strip_newline_in_stdout: bool = True,
         **subprocess_kwargs: Any,
     ) -> Union[str, bytes, Tuple[int, Union[str, bytes], str], AutoInterrupt]:
-        """Handles executing the command on the shell and consumes and returns
-        the returned information (stdout)
+        """Handles executing the command and consumes and returns the returned
+        information (stdout)
 
         :param command:
             The command argument list to execute.
-            It should be a string, or a sequence of program arguments. The
+            It should be a sequence of program arguments, or a string. The
             program to execute is the first item in the args sequence or string.
 
         :param istream: