Issue:
[BUG] Failing unit tests for Routing

### Bug Description

Certain unit tests in the `euclid` and `kgraph_utils` crates are failing.

**euclid**
```
test dssa::analyzer::tests::test_exhaustive_negation_detection ... FAILED
test frontend::dir::test::test_consistent_dir_key_naming ... FAILED
```

**kgraph_utils**
```
test mca::tests::test_sandbox_applepay_bug_usecase ... FAILED
```

### Expected Behavior

All unit tests should pass.

### Actual Behavior

Some tests fail owing to being outdated or due to a code discrepancy.

### Steps To Reproduce

1. Clone the main branch
2. Run the unit tests for the `euclid` and `kgraph_utils` crates

### Context For The Bug

_No response_

### Environment

Local

### Have you spent some time checking if this bug has been raised before?

- [X] I checked and didn't find a similar issue

### Have you read the Contributing Guidelines?

- [X] I have read the [Contributing Guidelines](https://github.com/juspay/hyperswitch/blob/main/docs/CONTRIBUTING.md)

### Are you willing to submit a PR?

Yes, I am willing to submit a PR!

Resolution:
<think>
PR Context:
- Title: fix(routing/tests): fix unit tests for routing
- Merged: 2024-04-24T09:39:37Z
- Files changed: 3 files
- Commits: 1 commits

Implementation approach:
## Type of Change
<!-- Put an `x` in the boxes that apply -->

- [x] Bugfix
- [ ] New feature
- [ ] Enhancement
- [ ] Refactoring
- [ ] Dependency updates
- [ ] Documentation
- [ ] CI/CD

## Description
<!-- Describe your changes in detail -->
This PR fixes failing unit tests for routing, either by updating outdated tests, or resolving code discrepancies. See #4437 for more info on failing tests.

### Additional Changes

- [ ] This PR modifies the API contract
- [ ] This PR mod
</think>

To implement this, you'll need to modify:


**Detailed Implementation:**


**Commit 1:** fix(routing/tests): fix unit tests for routing (#4438)
Files to modify:


**crates/euclid/src/dssa/analyzer.rs**
  Modify existing code

**crates/euclid/src/frontend/dir.rs**
  Modify existing code

**crates/kgraph_utils/src/mca.rs**
  Modify existing code