OCPBUGS-31247: Remove "(for user-provisioned installations)" reference for accepting CSRs on etcd restore procedure

This PR removes the above mentioned parenthesis and also improves
the technical description of the CSRs mentioned at that step.

Author: palonsoro

modules/dr-restoring-cluster-state.adoc

@@ -298,8 +298,8 @@ csr-4hl85   13m    kubernetes.io/kube-apiserver-client-kubelet   system:servicea
 csr-zhhhp   3m8s   kubernetes.io/kube-apiserver-client-kubelet   system:serviceaccount:openshift-machine-config-operator:node-bootstrapper   Pending <2>
 ...
 ----
-<1> A pending kubelet service CSR (for user-provisioned installations).
-<2> A pending `node-bootstrapper` CSR.
+<1> A pending kubelet serving CSR, requested by the node for the kubelet serving endpoint.
+<2> A pending kubelet client CSR, requested with the `node-bootstrapper` node bootstrap credentials.
 
 .. Review the details of a CSR to verify that it is valid by running:
 +