[Task] Update Azure OIDC guide

[toriancrane]

Draft PR

[toriancrane]

Unlike AWS, there does not currently appear to be a way to seamlessly run Azure CLI commands by exposing credential environment variables from a Pulumi ESC environment file. From this thread:

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This conversation took place a few weeks ago, so I sent a message to the esc slack channel to see if there are any updates with this functionality.

[toriancrane]

Still blocked on this activity until I hear back from Engineering.

The way that I currently understand how this works is that users must first run:

esc run pulumi/my-dev-env-2 -- az login \
--service-principal -u '${azure.login.clientId}' \
--tenant '${azure.login.tenantId}' \
--federated-token '${azure.login.oidc.token}' 

Before being able to run other az cli commands like this:

az vm list

There doesn't seem to be a way to specify credentials flags for a command like az vm list.

Further, any time the OIDC token expires, users would have to re-run the first command shown above, and quite frankly that is way more convoluted than just running az login.