Using Change Sets Causes "Internal Failure"

To reproduce:
```
Resources:
CommandRunner:
Type: 'AWSUtility::CloudFormation::CommandRunner'
Properties:
Command: echo 1 > /command-output.txt
```
1. Create stack with template above
2. Modify to "echo 2", create change set
3. Execute change set
4. Observe the CommandRunner resource fails with "Internal Failure"

Start by reproducing the failure with the template and sequence in the issue, then compare a direct update with execution through a change set. Trace the CommandRunner resource-provider entry point and its update handling to identify where the internal failure occurs. Done means executing the change set completes successfully and applies the changed command.

Written by the indexing model from the issue text.