Synapse Notebook Create vs Import difference is not stated.

Both "az synapse notebook create" and "az synapse notebook import" use the same description. It is not clear if there is a difference, or when one should be used instead of the other.

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#### Document Details

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* ID: d77ca694-fc52-26cb-5b54-f1ed409aa158
* Version Independent ID: 213683cd-f6f1-f18d-fbc5-bde1d40a3dec
* Content: [az synapse notebook](https://docs.microsoft.com/en-us/cli/azure/synapse/notebook?view=azure-cli-latest)
* Content Source: [latest/docs-ref-autogen/synapse/notebook.yml](https://github.com/MicrosoftDocs/azure-docs-cli/blob/main/latest/docs-ref-autogen/synapse/notebook.yml)
* GitHub Login: @rloutlaw
* Microsoft Alias: **routlaw**