Correct typo

readme.md

@@ -4,7 +4,7 @@
 ## Description
 A helper/utility script to be imported by other scripts.
 
-Intended to hold very common functionality (that's surprisingly not build into bash) such as string upper/lower,
+Intended to hold very common functionality (that's surprisingly not built into bash) such as string upper/lower,
 and checking current user value, and prompts of yes/no user input.