Add OSV scanner to GitHub Actions

[geekygirlsarah]

Description

Add the OSV scanner to GitHub Actions, as both a PR and a scheduled scan, to ensure outdated packages get updated.

Requirements

1. A YAML file for running OSV on each PR
2. A YAML file for running OSV on a scheduled time (maybe once a week?)

Additional Notes

Scheduled scan: https://github.com/google/osv-scanner-action/#scheduled-scan
Scan on PR: https://github.com/google/osv-scanner-action/#scan-on-pull-request