Please clarify how to pass the SSH public key

Please clarify or provide an example of how to pass the SSH public key in parameter --admin-user-ssh-key

I have tried providing the path to a .pub file in my ~/.ssh folder but this is not working - I get the error "The specified value for property Cluster.Properties.UserAccountSettings.AdminUserSshPublicKey is not a valid SSH Public Key. A valid SSH Public Key must be a base64 encoded valid RSA key or DSA key"

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* ID: e203eb0b-1c78-a76e-62e7-eddeeffdf0e3
* Version Independent ID: 38721d5a-59f3-24d0-3a76-fdcda10bd9c7
* Content: [az ml computetarget create](https://docs.microsoft.com/en-us/cli/azure/ext/azure-cli-ml/ml/computetarget/create?view=azure-cli-latest#ext-azure-cli-ml-az-ml-computetarget-create-amlcompute)
* Content Source: [latest/docs-ref-autogen/ext/azure-cli-ml/ml/computetarget/create.yml](https://github.com/MicrosoftDocs/azure-docs-cli/blob/live/latest/docs-ref-autogen/ext/azure-cli-ml/ml/computetarget/create.yml)
* GitHub Login: @rloutlaw
* Microsoft Alias: **routlaw**