Using Kubernetes secrets with envFrom for thanos

[nickmhankins]

We have AWS S3 credentials stored in a secret so Thanos object storage can authenticate with S3.

I was hoping for something like this, but no dice:

      prometheus+: {
        thanos: {
          version: '0.24.0',
          image: 'quay.io/thanos/thanos:v0.24.0',
          objectStorageConfig: {
            key: 'thanos.yaml'
            name: 'thanos-objectstorage'
          },
          envFrom: [{
             secretRef:{
               name: 'thanos-s3-keys',
            },
          }],
        },
      },