Fix typos

exercises/02_functions/functions5.rs

@@ -1,4 +1,4 @@
-// TODO: Fix the function body without chaning the signature.
+// TODO: Fix the function body without changing the signature.
 fn square(num: i32) -> i32 {
     num * num;
 }

solutions/02_functions/functions5.rs

@@ -1,5 +1,5 @@
 fn square(num: i32) -> i32 {
-    // Removed the semicolon `;` at the end of the line below to implicitely return the result.
+    // Removed the semicolon `;` at the end of the line below to implicitly return the result.
     num * num
 }