* chore: AzureMonitor typescript typings

Removes some types and using @grafana/ui types instead.
Adds some typing for the AzureMonitor query.

Also adds a getSubscriptions function that will used in the query
editor.

* fix: AzureMonitor adds back editor for annotation queries

This must have been broken for a month or more. Now possible to
edit annotation queries again.

* feat: Azure Monitor - support for multiple subscriptions

Adds a new dropdown for subscriptions in the query editor.

Defaults to the subscription id in jsonData for queries
that have no subscription id.

* feat: adds Azure Logs multi subscriptions support

The subscription id is needed for fetching the list of
workspaces. Adds support to the Log Analytics datasource
and to the annotations for Log Analytics to be able to
choose between multiple subscriptions.

* feat: AzureMonitor config page with multiple subs

Adds support for multiple subscriptions for the different
variations of configuring Azure Monitor and Azure Logs.

To be able to show a list of subscriptions, the config
has to be saved first - the plugin route fetches the
tenant id, client id and client secret from the database
so a call to get subscriptions requires that those
fields are saved first. If the page has not saved then
the use can manually paste in a subscription id.

* feat: support for multi subs in Azure Monitor variables

Adds an optional subscription parameter to the template
variable macros. Also adds a Subscriptions macro.

* fix: remove some implicit anys from tests