Unknown exception while processing rule WS1002

[nmoutschen]

When scanning all repositories in aws-samples for potential bugs, I found several E0002 errors from cfn-lint regarding rule WS1002:

aws-samples/digital-user-engagement-reference-architectures:digital-user-engagement-reference-architectures-master/cloudformation/Connect_as_a_Channel.yaml: E0002: Unknown exception while processing rule WS1002: unhashable type: 'dict_node_intrinsic_sub'
aws-samples/digital-user-engagement-reference-architectures:digital-user-engagement-reference-architectures-master/cloudformation/External_Attributes.yaml: E0002: Unknown exception while processing rule WS1002: unhashable type: 'dict_node_intrinsic_sub'
aws-samples/digital-user-engagement-reference-architectures:digital-user-engagement-reference-architectures-master/cloudformation/External_Templates.yaml: E0002: Unknown exception while processing rule WS1002: unhashable type: 'dict_node_intrinsic_sub'
aws-samples/aws-elemental-mediatailor-tools:aws-elemental-mediatailor-tools-master/CloudFormation/CustomMetrics/EMTMetrics.json: E0002: Unknown exception while processing rule WS1002: unhashable type: 'dict_node'
aws-samples/aws-service-catalog-reference-architectures:aws-service-catalog-reference-architectures-master/serverless/sc-serverless-lambda.yml: E0002: Unknown exception while processing rule WS1002: unhashable type: 'dict_node_intrinsic_sub'
aws-samples/amazon-workmail-lambda-templates:amazon-workmail-lambda-templates-master/workmail-chat-bot-python/template.yaml: E0002: Unknown exception while processing rule WS1002: unhashable type: 'dict_node'
aws-samples/amazon-workmail-lambda-templates:amazon-workmail-lambda-templates-master/workmail-hello-world-python/template.yaml: E0002: Unknown exception while processing rule WS1002: unhashable type: 'dict_node'
aws-samples/amazon-workmail-lambda-templates:amazon-workmail-lambda-templates-master/workmail-restricted-mailboxes-python/template.yaml: E0002: Unknown exception while processing rule WS1002: unhashable type: 'dict_node'
aws-samples/amazon-workmail-lambda-templates:amazon-workmail-lambda-templates-master/workmail-stop-mail-storm/template.yaml: E0002: Unknown exception while processing rule WS1002: unhashable type: 'dict_node'
aws-samples/amazon-workmail-lambda-templates:amazon-workmail-lambda-templates-master/workmail-translate-email/template.yaml: E0002: Unknown exception while processing rule WS1002: unhashable type: 'dict_node'
aws-samples/amazon-workmail-lambda-templates:amazon-workmail-lambda-templates-master/workmail-update-email/template.yaml: E0002: Unknown exception while processing rule WS1002: unhashable type: 'dict_node'
aws-samples/amazon-workmail-lambda-templates:amazon-workmail-lambda-templates-master/workmail-wordpress-python/template.yaml: E0002: Unknown exception while processing rule WS1002: unhashable type: 'dict_node'
aws-samples/arc325-multiple-accounts-workshop:arc325-multiple-accounts-workshop-master/templates/centralized-log-analytics.yml: E0002: Unknown exception while processing rule WS1002: unhashable type: 'dict_node'
aws-samples/arc325-multiple-accounts-workshop:arc325-multiple-accounts-workshop-master/templates/vpc-flow-logs_instance_logs.yml: E0002: Unknown exception while processing rule WS1002: unhashable type: 'dict_node'