Issue#426 Added aria-label attribute to the Search button element

[adityaj07]

As mentioned, I've added an aria-label attribute to the Search button for better accessibility. I also ran an audit with lighthouse and the accessibility score has increased from 92 to 97 as the issue seems to be solved now.

[runemadsen]

Thanks so much for this! Approved 👍

[SableRaf]

Thanks @adityaj07!

@runemadsen: Could you review this small change? I'm still not super familiar with the syntax for those react components.