Disable creation of new on-demand alerts after the limit has been reached

[obostjancic]

Basically prevent SENTRY-3MRN from happening

[ArthurKnaus]

We will disable on-demand alert creation in the FE once the limit is reached.
Similar to the current warning, we will display an error message instead.

Existing on demand warning:

Error message once the limit was reached:

We don’t routinely collect metrics for “property1”[, … “propertyX]” and you’ve already reached the limit of alerts with advanced filters for your organization.

In this case, the icon should be red and the create button should be disabled.