Add SSL Cert Functionality

[nivibilla]

Adds a verify parameter to the RuntimeEndpoint and modifies utils.py.

can be used like

runtime = sgl.RuntimeEndpoint(url, verify='./ca_bundle.crt')

This doesn't modify any of the openai python interactions since we can just do this instead

import httpx
import openai
client = openai.Client(
    base_url=url + "/v1",
    http_client = httpx.Client(verify='./ca_bundle.crt'),
    api_key='none'
    )

# Chat completion
response = client.chat.completions.create(
    model="default",
    messages=[
        {"role": "system", "content": "You are a helpful AI assistant"},
        {"role": "user", "content": "List 3 countries and their capitals."},
    ],
    temperature=0,
    max_tokens=64,
)
print(response)