Put shibboleth config into git repo so we can track changes

Currently, we have some config files in S3 bucket. It's easy to deploy at the time. However, it's hard to make and track changes.

• shib_config.tar.gz

It would be nice to make those config files git repos, so we can track changes easily.

In addition, it will be nice to setup pipeline that when we update config files, it trigger a new build and deploy to include the change.

After comment:

The pipeline now:

1. do xmllint to verify all xml files are valid without syntax error.
2. Once the change is committed on main branch, i.e. merged, there will be a button shown in pipeline to upload the tarball, shib_conf.tar.gz to S3 bucket.