Improve error message of BCP395

[Tapanila]

Is your feature request related to a problem? Please describe. I had following provider defined on bicep:

provider '[email protected]'

I received nice linter error BCP395 with following message: "Declaring provider namespaces using the <providerName>@<version> expression has been deprecated. Please use an identifier instead."

It took me a while to undersand this error message and trial and error to fix it.

Describe the solution you'd like

I would like the error message to be improved. and I think it would make more sense if it would be following:

"Declaring provider namespaces using the "provider '<providerName>@<version>'" expression has been deprecated. Please use an 'provider <providerName>' instead."