Helix rest disablePartitions API fails to parse ALL_RESOURCE as the key

### Describe the bug
We introduced a feature that uses the `ALL_RESOURCE` placeholder to disable all resources, allowing the controller to treat the instance as DISABLED, even if its specific instance operation is NOT DISABLED. However, it seems that `ALL_RESOURC`E is not being correctly interpreted by Helix-REST.

### To Reproduce
Sending a call to disablePartitions while setting the resources to be `ALL_RESOURCE`

### Expected behavior
A clear and concise description of what you expected to happen.
Calling disablePartitions with `ALL_RESOURCE` should work

### Additional context
N/A

Start by tracing the Helix-REST disablePartitions API handling for the ALL_RESOURCE key and reproduce the reported request. Verify how the key is parsed and add or update coverage for this call; done means disablePartitions accepts ALL_RESOURCE and applies the expected disabled-resource behavior.

Written by the indexing model from the issue text.