Add snyk security scanning to this repository

[JPZ13]

@sarabala1979 and @terrytangyuan requested that we add Snyk security scanning to this repo in the weekly contributors meeting. They suggested adding something similar to the security scanning action in Argo Workflows. Here is a link to the file

To complete:

• Add a snyk.yml file to this repo in order for it to run in a Github action
• Configure it to work appropriately on this repo

[JPZ13]

I'd like to assign this to @rohankmr414 but don't have access to assign

[terrytangyuan]

I don't know how Snyk works but the Go version in this repo does not seem to impact the security of argo-workflows. I haven't seen any alerts around it.