Update to new GPT 3.5-Turbo type

From our existing ChatDev typing.py:

class ModelType(Enum):
    GPT_3_5_TURBO = "gpt-3.5-turbo-16k-0613"
    GPT_3_5_TURBO_NEW = "gpt-3.5-turbo-16k"
    GPT_4 = "gpt-4"
    GPT_4_32k = "gpt-4-32k"
    GPT_4_TURBO = "gpt-4-turbo"
    GPT_4_TURBO_V = "gpt-4-turbo"

    STUB = "stub"

    @property
    def value_for_tiktoken(self):
        return self.value if self.name != "STUB" else "gpt-3.5-turbo-16k-0613"

Where in official OpenAI's models page:

The current GPT 3.5-Turbo types (gpt-3.5-turbo-16k-0613 & gpt-3.5-turbo-16k) used in ChatDev is considered legacy and will be deprecated very soon (next week).

Advise to update the types to remain updated to use OpenAI's latest GPT 3.5-Turbo, by just using the value "gpt-3.5-turbo" should be sufficient (which is already supports 16k context window by default).

Start in the existing ChatDev typing.py file and inspect the ModelType enum and its references. Update the legacy GPT-3.5-Turbo model value to the current gpt-3.5-turbo value, then verify that the affected model references still resolve correctly.