aws-cdk: Replace `__dirname`

### Describe the feature

Replace the global variable `__dirname` used with an alternative that properly handles special characters and is more widely supported

### Use Case

I've seen issues in #21161, and #18470, and may be running into issues myself due to path resolution shenanigans on my system with the `__dirname` global variable.

### Proposed Solution

It seems feasible from my limited knowledge of Node.js to use `path.dirname(url.fileURLToPath(import.meta.url))` instead, given its introduction back in Node.js 10.12.

### Other Information

_No response_

### Acknowledgements

- [ ] I may be able to implement this feature request
- [ ] This feature might incur a breaking change

### CDK version used

2.80.0

### Environment details (OS name and version, etc.)

NixOS 23.05

No files or tests are named. Start by locating the repository's uses of __dirname and reviewing the Node.js path-resolution context around them. Done means the relevant uses no longer rely on __dirname, handle special characters correctly, and the existing tests pass.

Written by the indexing model from the issue text.