Escape the distributed contribution command settings (#653)

* update install.md by adding the missing ```. (#649)

* Escape the distributed contribution command settings

Fields passed to the distributed contribution command were unescaped,
which caused some parameters (such as passwords) to close the command
quote early.

---------

Co-authored-by: hiuxia <98009342+hiuxia@users.noreply.github.com>

katrain/core/contribute_engine.py

@@ -72,7 +72,7 @@ def __init__(self, katrain):
         self.max_buffer_games = 2 * settings_dict["maxSimultaneousGames"]
         settings = {f"{k}={v}" for k, v in settings_dict.items()}
         self.command = shlex.split(
-            f'"{exe}" contribute -config "{cfg}" -base-dir "{base_dir}" -override-config "{",".join(settings)}"'
+            f'"{exe}" contribute -config "{cfg}" -base-dir "{base_dir}" -override-config {shlex.quote(",".join(settings))}'
         )
         self.start()