Promoting Azure best practices

[pakrym]

There is a set of best practices that we as Azure are recommending to customers. For example, using the managed identity for secretless auth. It would be great if we could allow customers to opt into getting diagnostics about best practices they like.

For example the following snippet would produce a diagnostic

resource frontend 'Microsoft.Web/sites@2021-01-15' = {
}

With a hot fix resulting in:

resource frontend 'Microsoft.Web/sites@2021-01-15' = {
  identity: {
    type: 'SystemAssigned'
  }
}

Maybe we can integrate with some Azure Advisor rules to shift suggestions to the development time.

[asears]

Also see https://azure.github.io/PSRule.Rules.Azure/using-bicep/ and https://azure.github.io/PSRule.Rules.Azure/validating-locally/
and https://github.com/Microsoft/PSRule-pipelines

[BernieWhite]

Related to: #3890