warn about Deprecating azure connections from train

Signed-off-by: Sathish <sbabu@progress.com>

Author: sathish-progress

lib/train/transports/azure.rb

@@ -8,6 +8,7 @@
 require "train/transports/helpers/azure/file_credentials"
 require "train/transports/clients/azure/graph_rbac"
 require "train/transports/clients/azure/vault"
+require "active_support"
 
 module Train::Transports
   class Azure < Train.plugin(1)
@@ -31,6 +32,7 @@ class Connection < BaseConnection
       DEFAULT_FILE = ::File.join(Dir.home, ".azure", "credentials")
 
       def initialize(options)
+        ActiveSupport::Deprecation.warn("Azure Connection with Train will be deprecated from Inspec 6")
         @apis = {}
 
         # Override for any cli options