main: remove ineffective "general" group description

Since this is not the first `getgroup` call on this name, the
description is just ignored. It's also not really accurate, as the
"general" group contains a bunch of stuff. So let's just keep "general"
as the description for now.

Author: bluetech

src/_pytest/main.py

@@ -56,7 +56,7 @@
 
 
 def pytest_addoption(parser: Parser) -> None:
-    group = parser.getgroup("general", "Running and selection options")
+    group = parser.getgroup("general")
     group._addoption(  # private to use reserved lower-case short option
         "-x",
         "--exitfirst",