CloudFormation `Fn::ForEach` throws issues - Stack Overflow

I'd like to use Fn::ForEach available in CloudFormation. In the documentation we can find this sentence:

Fn::ForEach can contain other intrinsic functions, including Fn::ForEach itself, and be used within the Conditions, Outputs, Resources (including the resource properties) sections

...
Mappings:
  FancyMapping:
    a:
      Values:
        - optionAValue1
    b:
      Values:
        - optionAValue1
    c:
      Values:
        - optionAValue1
...

Resources:
    ...
    - PolicyName: SSMPolicy
      PolicyDocument:
        Version: 2012-10-17
        Statement:
          - Effect: Allow
            Action:
              - ssm:GetParameter
            Resource:
              Fn::ForEach:Resources:
                - Iterator
                - !FindInMap [ FancyMapping, !Ref SomeChoice, Values ]
                - !Sub arn:aws:ssm:${Iterator}:${AWS::AccountId}:*

Unfortunately when I run sam validate -t <template.yaml> --region <region> --lint. It will throw an error that the Iterator cannot be found in Sub function.

Is it possible to use this Fn::ForEach for Resource properties, or not?