SNOW-1967309: SNOW-1927956: Add support for workload identity federation

[sfc-gh-pmansour]

What is the current behavior?

Snowflake supports external OAuth but not workload identity federation.

What is the desired behavior?

Support authenticating to Snowflake using native identity from Azure, AWS, GCP or other platforms that support generic OIDC ID tokens.

How would this improve snowflake-connector-python?

Allow for simpler and more secure configuration without the need to explicitly manage secrets.

References and other background

go/wif

[sfc-gh-dszmolka]

thanks for the PR :) #2203

[nicornk]

🎉🚀