EULA Content in k8s-extension

### Related command
`az k8s-extension create`

### Extension name (the extension in question)

[k8s-extension](https://github.com/Azure/azure-cli-extensions/tree/main/src/k8s-extension)

### Description of issue (in as much detail as possible)

Our team is working to get [ AKS extension for Dapr](https://docs.microsoft.com/en-us/azure/aks/dapr) to GA. As a part of it, we have been told to output [EULA content](https://msazure.visualstudio.com/One/_wiki/wikis/One.wiki/188216/EULA-content) at the top of the console output. After discussing, it was decided to output this whenever `az k8s-extension create` command is used.

1. With a bit of code overview, I think the log statement should be added here: https://github.com/Azure/azure-cli-extensions/blob/4305dbc5162756e1e9867bd4cb80a08e601ebb49/src/k8s-extension/azext_k8s_extension/custom.py#L90 Is it correct?

2. Given EULA content is a standard, shouldn't it be in some base class extending to all cli extensions? I couldn't find it in the repo.