ci: run LSIF on all main and release branch pushes
Created by: bobheadxi
We don't want to clog up the pipeline with LSIF runs on every push, but I also think we are good to run it on pushes to main. This change adjusts the condition to a few long-lived branches and pull requests that change certain paths.
Follow-up to https://github.com/sourcegraph/sourcegraph/commit/b41121d635581f64ac215ecbe1d6f3c1cdacf069 not triggering an LSIF upload for demo