`[TODO]`: Benchmark `iter` intensive parts of the file_io

There are two main functions that read over file data and they might be wasting a lot of resources with unoptimized `iter()` functionality (e.g., not using `nth()`, overusing `map()`, etc.). 

the main places to benchmark with large input files and start to find optimization are:
- `FileChanges::from_file_data`
- `read_file_data_and_check_for_match`