Cloud formation template deploy fails (first command of the tutorial)

[fabiobeoni]

Running from Cloud Shell

aws cloudformation create-stack --stack-name Observability-Workshop \
   --template-body file://codepipeline-stack.yaml \
   --capabilities CAPABILITY_NAMED_IAM \
   --parameters ParameterKey=UserRoleArn,ParameterValue=$(aws iam get-role --role-name $(aws sts get-caller-identity --query Arn --output text | awk -F/ '{print $(NF-1)}') --query Role.Arn --output text) 

Error:

An error occurred (ValidationError) when calling the GetRole operation: The specified value for roleName is invalid. It must contain only alphanumeric characters and/or the following: +=,.@_-

The first nested command aws sts get-caller-identity returns my user arn, the second one aws iam get-role --role-name uses my user Arn as value of the --role-name and that gets the error above.

[fabiobeoni]

Actually the command runs, but the stack deploy misses the UserRoleArn param value: