Unify random string generation to use random.choices

Replace list comprehension pattern with simpler random.choices(k=10).

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: laughingman7743

tests/__init__.py

@@ -28,7 +28,7 @@ def __init__(self):
         )
         self.default_work_group = os.getenv("AWS_ATHENA_DEFAULT_WORKGROUP", "primary")
         self.schema = "pyathena_test_" + "".join(
-            [random.choice(string.ascii_lowercase + string.digits) for _ in range(10)]
+            random.choices(string.ascii_lowercase + string.digits, k=10)
         )
         self.s3_filesystem_test_file_key = (
             f"{self.s3_staging_key}{self.schema}/filesystem/test_read/test.dat"

tests/pyathena/arrow/test_async_cursor.py

@@ -275,7 +275,7 @@ def test_no_ops(self):
     )
     def test_empty_result(self, async_arrow_cursor):
         table = "test_pandas_cursor_empty_result_" + "".join(
-            [random.choice(string.ascii_lowercase + string.digits) for _ in range(10)]
+            random.choices(string.ascii_lowercase + string.digits, k=10)
         )
         query_id, future = async_arrow_cursor.execute(
             f"""

tests/pyathena/arrow/test_cursor.py

@@ -476,7 +476,7 @@ def test_show_columns(self, arrow_cursor):
     )
     def test_empty_result(self, arrow_cursor):
         table = "test_arrow_cursor_empty_result_" + "".join(
-            [random.choice(string.ascii_lowercase + string.digits) for _ in range(10)]
+            random.choices(string.ascii_lowercase + string.digits, k=10)
         )
         df = arrow_cursor.execute(
             f"""

tests/pyathena/pandas/test_async_cursor.py

@@ -424,7 +424,7 @@ def test_show_columns(self, async_pandas_cursor, parquet_engine, chunksize):
     )
     def test_empty_result_ddl(self, async_pandas_cursor, parquet_engine, chunksize):
         table = "test_pandas_cursor_empty_result_" + "".join(
-            [random.choice(string.ascii_lowercase + string.digits) for _ in range(10)]
+            random.choices(string.ascii_lowercase + string.digits, k=10)
         )
         query_id, future = async_pandas_cursor.execute(
             f"""

tests/pyathena/pandas/test_cursor.py

@@ -842,7 +842,7 @@ def test_show_columns(self, pandas_cursor, parquet_engine, chunksize):
     )
     def test_empty_result_ddl(self, pandas_cursor, parquet_engine, chunksize):
         table = "test_pandas_cursor_empty_result_" + "".join(
-            [random.choice(string.ascii_lowercase + string.digits) for _ in range(10)]
+            random.choices(string.ascii_lowercase + string.digits, k=10)
         )
         df = pandas_cursor.execute(
             f"""