Empty change list when only stack tags are changing

[viraptor]

When updating tags on a stack which doesn't contain any taggable resources, the output is confusing:

Stack diff: No changes
Parameters diff: No changes
 * can not tell if NoEcho parameters are different.

========================================
Proposed change set:
========================================
Apply change set (y/n)?

When accepted, the stack is updated/reported as expected:

2020-02-05 15:55:35 +1100 tsunami-waf AWS::CloudFormation::Stack UPDATE_IN_PROGRESS User Initiated
2020-02-05 15:55:40 +1100 tsunami-waf AWS::CloudFormation::Stack UPDATE_COMPLETE_CLEANUP_IN_PROGRESS 
2020-02-05 15:55:40 +1100 tsunami-waf AWS::CloudFormation::Stack UPDATE_COMPLETE

[patrobinson]

Sounds like a CloudFormation issue? Not sure how we can improve this.