gh-95573: Reduce test data size in test_asyncio/test_ssl.py - #95668

Task exception was never retrieved
future: <Task finished name='Task-79' coro=<TestSSL.test_create_server_ssl_over_ssl.<locals>.handle_client() done, defined at cpython/Lib/test/test_asyncio/test_ssl.py:1039> exception=OSError(55, 'No buffer space available')>
Traceback (most recent call last):
  File "cpython/Lib/test/test_asyncio/test_ssl.py", line 1042, in handle_client
    data = await reader.readexactly(len(A_DATA))
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "cpython/Lib/asyncio/streams.py", line 728, in readexactly
    await self._wait_for_data('readexactly')
  File "cpython/Lib/asyncio/streams.py", line 522, in _wait_for_data
    await self._waiter
  File "cpython/Lib/asyncio/selector_events.py", line 1049, in write
    n = self._sock.send(data)
        ^^^^^^^^^^^^^^^^^^^^^
OSError: [Errno 55] No buffer space available