Caching access token during BrowserIdcAuthPlugin authentication for subsequent/parallel session requests

Currently, running SQL queries via `BrowserIdcAuthPlugin` is done on a per-session basis. This can be tiresome when running queries across different sessions in parallel (e..g, dbt), where multiple browser pop-ups are triggered throughout the run duration. I would like to add a feature to cache the access token received during the token exchange process, so that future sessions will reuse the cached token instead of re-initializing a new session.

As the proposal involves storing the access token locally (whether it be via file/memory, plain-text/encrypted, etc.), would this be a security issue? Not sure if it would be a hard blocker before I open a PR for this feature proposal.