ci: setup IAM Roles and AWS Secrets Manager integration

[luislhl]

Acceptance Criteria

• Stop using secrets stored in Github, and get them from AWS Secrets Manager
• Create a separate Composite Actions and a Reusable Workflow to be reused in jobs: setup-python and deploy-reusable
• Use https://github.com/aws-actions/configure-aws-credentials to get temporary AWS Credentials for the job, instead of using permanent credentials stored in Github. The roles that will be assumed by Github Actions for this are being created in https://github.com/HathorNetwork/ops-tools/pull/872

TODO

• [x] Remove the secrets from Github

Security Checklist

• [ ] Make sure you do not include new dependencies in the project unless strictly necessary and do not include dev-dependencies as production ones. More dependencies increase the possibility of one of them being hijacked and affecting us.