chore: update golang tutorials to use v1 authored blobs

[jcstein]

these guides use v0 blobs and namespaces, but need to use v1 and authored blobs. update them:

1. golang + light node: https://docs.celestia.org/tutorials/golang-client-tutorial
2. double-check the rust + light node: https://docs.celestia.org/tutorials/rust-client-tutorial

[evan-forbes]

users recently asked about this so we might want to consider bumping it

[walldiss]

Signed blobs can be filtered by looping over all blobs in the namespace and selecting the ones with required signer.

	received, err := client.Blob.GetAll(ctx, height, namespace)
	for _, blob := range received {
		if bytes.Equal(blob.Signer(), []byte("my_signer")){
				// do smth
		}
	}

The signer field can also be checked with

blob.HasSigner()

[jcstein]

thank you @evan-forbes and @walldiss

[jcstein]

for this, @gbarros, let's first make sure our new WIP docs are accurate. once they are, port over the new version to the current docs so it can temporarily live as a resource, until new docs are live. sound good?