Update tutorial for Kubernetes on Hetzner with Cluster API

[abdulmajid3352]

Closes: #1434

• Improved clarity and formatting in the introduction section.
• Added detailed instructions for creating and verifying an SSH key for Hetzner Cloud.
• Included steps to wait for Cluster API components to be ready before proceeding.
• Clarified the process for creating a secret to enable communication with the Hetzner API.
• Updated instructions for generating and retrieving the kubeconfig for the workload cluster.

I have read and understood the Contributor's Certificate of Origin available at the end of
https://raw.githubusercontent.com/hetzneronline/community-content/master/tutorial-template.md
and I hereby certify that I meet the contribution criteria described in it.
Signed-off-by: Abdul Majid abdulmajid0079@hotmail.com

Tested locally using a kind cluster as explained in the doc:

➜  ~ k get clusters
NAME              CLUSTERCLASS   AVAILABLE   CP DESIRED   CP AVAILABLE   CP UP-TO-DATE   W DESIRED   W AVAILABLE   W UP-TO-DATE   PHASE         AGE   VERSION
hetzner-cluster                  True        3            3              3               3           3             3              Provisioned   14m   

[svenja11]

Thank you for the update @abdulmajid3352!