Add missing env variables and fix BYOK docs

[hutec]

Code of Conduct

• I have read and agree to the GitHub Docs project's Code of Conduct

What article on docs.github.com is affected?

https://docs.github.com/en/copilot/how-tos/copilot-cli/customize-copilot/use-byok-models

What part(s) of the article would you like to see updated?

• Add missing env variables (COPILOT_PROVIDER_BEARER_TOKEN, COPILOT_PROVIDER_WIRE_API, COPILOT_PROVIDER_AZURE_API_VERSION, COPILOT_PROVIDER_MODEL_ID, COPILOT_PROVIDER_WIRE_MODEL, COPILOT_PROVIDER_MAX_PROMPT_TOKENS, COPILOT_PROVIDER_MAX_OUTPUT_TOKENS)
• Fix Azure provider format: COPILOT_PROVIDER_BASE_URL=https://YOUR-RESOURCE-NAME.openai.azure.com/openai/deployments/YOUR-DEPLOYMENT-NAME should be https://YOUR-RESOURCE-NAME.openai.azure.com
• Add explanation for Azure provider specific env variables COPILOT_PROVIDER_MODEL_ID and COPILOT_PROVIDER_WIRE_MODEL

The env variables are improving the completeness of the docs.
The url fix makes the url simpler and removes the dependency on YOUR-DEPLOYMENT-NAME.

Additional information

No response

[Sharra-writes]

@hutec Checking with the CLI team to see if these fit in this article and that they're all accurate.

[github-actions]

Thanks for opening an issue! We've triaged this issue for technical review by a subject matter expert 👀