Add a security policy

[reedy]

Can someone please add a security policy to this repo?

See https://docs.github.com/en/code-security/getting-started/adding-a-security-policy-to-your-repository

Filed as part of https://phabricator.wikimedia.org/T292110

[miselico]

The security policy is now in place here: https://github.com/martaannaj/RecommenderServer/blob/main/SECURITY.md

[miselico]

Closing as the security review has now been completed. https://phabricator.wikimedia.org/T292110