vultr: rename prefix vr_to vultr_ (#43994)

* vultr: rename modules

* replace string vr_ with vultr_

* add deprecation warning

* fix sanity tests

* add changelog

lib/ansible/module_utils/vultr.py

@@ -30,6 +30,10 @@ def vultr_argument_spec():
 class Vultr:
 
     def __init__(self, module, namespace):
+
+        if module._name.startswith('vr_'):
+            module.deprecate("The Vultr modules were renamed. The prefix of the modules changed from vr_ to vultr_", version='2.11')
+
         self.module = module
 
         # Namespace use for returns