This PR introduces a CI job to periodically scan the OpenVDB repositoryfor security vulernatiblities. This CI job requires coordination withJohn Mertic (jmertic) and/or the OpenVDB maintainers to add both the`SNYK_ORG` and `SNYK_TOKEN` GitHub secrets to the GitHub configuration.Once these serets are added, then this PR can be merged with theappropriate review/approvals. The Snyk tool can be run on the commandline at any time using:```bashsnyk auth ${SNYK_TOKEN}Your account has been authenticated. Snyk is now ready to be used.snyk test --unmanaged --org=${SNYK_ORG}Testing /Users/ddeal/projects/go/src/github.com/dealako/openvdb...Tested 1 dependency for known issues, found 0 issues.snyk monitor --unmanaged --org=${SNYK_ORG}Monitoring /Users/ddeal/projects/go/src/github.com/dealako/openvdb (openvdb)...Explore this snapshot athttps://app.snyk.io/org/openvdb/project/${SNY_ORG}/history/4c82fd74-757b-40f3-8522-803ae4f84e0fNotifications about newly disclosed issues related to these dependencies will be emailed to you.```Contact John Mertic (jmertic) to access the above secrets or to gainaccess to the Snyk console.Signed-off-by: David Deal <ddeal@linuxfoundation.org>