Condition reference inside RuleCondition in Rule block

### Resource Name

CloudFormation Rules Block

### Details

Rule-specific intrinsic function "Condition" cannot be used under Rules block of CloudFormation template.

**Expected Behavior:**
Can reference to a condition since it will return true or false in RuleCondition block for more flexible constraint validation
**Observed Behavior:**
Cannot reference to a condition
**Test case:**
```
Parameters:
Stream:
Type: String

Condition:
Testing: !Equals ['a', 'a']
Rules:
FirstRule:
RuleCondition: !Condition Testing
Assertions:
- AssertDescription: "Must have value"
Assert: !Not
- !Equals [ !Ref Stream, '' ]
```

Start with the CloudFormation Rules Block example in the issue and compare the documented behavior of RuleCondition with the Condition intrinsic function. There are no repository files, tests, or entry points named; done would require confirming whether condition references are supported and documenting or tracking the resulting coverage change.

Written by the indexing model from the issue text.