Migrations table in the rewards_api schema

What's Changed

• Bump docker/login-action from 1 to 2 by @dependabot in #4
• Bump docker/build-push-action from 2 to 3 by @dependabot in #5
• Migrations - use app schema for migrations table instead of public by @JamesReate in #7

Full Changelog: v0.1.1...v0.1.2