doc: Remove preview note from Resource policy documentation #1338 (#1339)

Author: maastha

cfn-resources/resource-policy/README.md

@@ -9,8 +9,6 @@ Resource for managing [Resource Policies](https://www.mongodb.com/docs/atlas/ref
 Set up an AWS profile to securely give CloudFormation access to your Atlas credentials.
 For instructions on setting up a profile, [see here](/README.md#mongodb-atlas-api-keys-credential-management).
 
-**NOTE:** Resource Policies is currently in Public Preview, if you want to use it, contact [MongoDB Support](https://www.mongodb.com/services/support) to enable `Atlas Resource Policies` Preview Feature in your organization.
-
 ## Attributes and Parameters
 
 See the [resource docs](./docs/README.md).