AZ CLI: Improve handling of npm install

[stevengum]

Tool

Name: az cli
Version: 2.0.53 (0.1.3)

Describe the bug

KuduClient.install_npm_dependencies() performs a request for Kudu to install the npm dependencies. However, npm install can take a long time and the client can timeout while waiting for the successful response from Kudu.

Expected behavior

Not have the KuduClient timeout due to npm install taking a long time. KuduClient timing out leads to an error that makes it seem like the publish failed (which it may or may not have).

[bug]

[stevengum]

Crosslink #895

[stevengum]

We are planning on improving the robustness around with 4.4, but in the meantime we have added a message warning the user that the connection timed out and that this is a known issue (and provided additional instructions on manually installing the npm dependencies.

[stevengum]

Closing via Azure/azure-cli#8445 and Azure/azure-cli#8711