fix: improve header validation

[Uzlopak]

takes the header validation logic from #932

[github-actions]

👋 Hi! Thank you for this contribution! Just to let you know, our GitHub SDK team does a round of issue and PR reviews twice a week, every Monday and Friday! We have a process in place for prioritizing and responding to your input. Because you are a part of this community please feel free to comment, add to, or pick up any issues/PRs that are labeled with Status: Up for grabs. You & others like you are the reason all of this works! So thank you & happy coding! 🚀

[G-Rath]

This doesn't really seem like an improvement to me as we're now only reporting a single missing header, and using more code to do so?

[Uzlopak]

@G-Rath

The benefit is to avoid creating arrays and strings, over and over.

[Uzlopak]

@G-Rath

What about now? It avoids as I wrote unneccessary array and string generation.

[wolfy1339]

I don't think we need to use binary here. Let's keep this simple....

[Uzlopak]

I actually want more performance.

[wolfy1339]

While more performance is always good. At what point do we really need to sacrifice readability and understanding for performance.
Let's keep it stupid simple