refactor(random): clean up imports and type hints

- Remove duplicate logger definition
- Add proper Self type hint for Python 3.11+
- Clean up redundant type checking imports
- Improve code organization

Author: tony

src/libtmux/test/random.py

@@ -10,8 +10,6 @@
     TEST_SESSION_PREFIX,
 )
 
-logger = logging.getLogger(__name__)
-
 if t.TYPE_CHECKING:
     import sys
 
@@ -24,12 +22,6 @@
 
 logger = logging.getLogger(__name__)
 
-if t.TYPE_CHECKING:
-    import sys
-
-    if sys.version_info >= (3, 11):
-        pass
-
 
 class RandomStrSequence:
     """Factory to generate random string."""