chore(test): Replace temp._RandomNameSequence with separate function

This was a private API and not mypy compatible (not in typeshed)

Author: tony

libtmux/test.py

@@ -2,7 +2,7 @@
 import contextlib
 import logging
 import os
-import tempfile
+import random
 import time
 import warnings
 from typing import Callable, Optional
@@ -15,7 +15,19 @@
 RETRY_TIMEOUT_SECONDS = int(os.getenv("RETRY_TIMEOUT_SECONDS", 8))
 RETRY_INTERVAL_SECONDS = float(os.getenv("RETRY_INTERVAL_SECONDS", 0.05))
 
-namer = tempfile._RandomNameSequence()
+
+class RandomStrSequence:
+    def __init__(self, characters: str = "abcdefghijklmnopqrstuvwxyz0123456789_"):
+        self.characters: str = characters
+
+    def __iter__(self):
+        return self
+
+    def __next__(self):
+        return "".join(random.sample(self.characters, k=8))
+
+
+namer = RandomStrSequence()
 current_dir = os.path.abspath(os.path.dirname(__file__))
 example_dir = os.path.abspath(os.path.join(current_dir, "..", "examples"))
 fixtures_dir = os.path.realpath(os.path.join(current_dir, "fixtures"))