fix(grammar): fix minor typo in jtag part 4 (#448)

### Summary

 There is a minor grammar issue in the article excerpt. This PR fixes it.

 ### Test Plan

 Visual check.

_posts/2024-03-29-diving-into-jtag-part-4.md

@@ -10,7 +10,7 @@ tags: [arm, cortex-m, mcu, debugging, debugger]
 In the previous article of this series, we briefly touched on how `.bsd` files
 written in Boundary Scan Description Language (BSDL) describe the structure of
 the boundary scan chain and the instruction set. In this article, we will
-examine this language's syntax more closely before seeing how they are leveraged
+examine this language's syntax more closely before seeing how `.bsd` files are leveraged
 in JTAG testing in the next article.
 
 <!-- excerpt end -->