docs: typo

Author: Alfie John

src/doc/trpl/crates-and-modules.md

@@ -258,7 +258,7 @@ fn goodbye() -> String {
 
 (This is "Sayōnara", if you're curious.)
 
-Now that we have our some functionality in our crate, let's try to use it from
+Now that we have some functionality in our crate, let's try to use it from
 another crate.
 
 # Importing External Crates