This makes two changes:
* Reduces action instance type to 16 cores. This will half the cost without a significant speed difference
* Switch from `make full` to CodeQL Auto Build. This speeds up the build by about 10 minutes. I confirmed there is not a reduction in the scan coverage
We still plan to address this root issue, and are tracking making CodeQl faster so it can be a required PR check: https://github.com/gravitational/SecOps/issues/269
However, until then we need to switch this job to be a scheduled task rather than on every PR and push. This is partly cost motivated, but also we are already hitting our timeouts. This PR also increases the analysis timeout so that the daily job can be sure to complete.
Mike Jensen