fix typos

Author: aspeddro

pages/docs/manual/latest/exception.mdx

@@ -136,7 +136,7 @@ if (exit === 1) {
 
 ### `Invalid_argument`
 
-Used to check if argument is valid. This exception takes a string
+Used to check if argument is valid. This exception takes a string.
 
 <CodeTab labels={["ReScript", "JS Output"]}>
 ```res example
@@ -270,7 +270,7 @@ catch (raw_loc){
 ### `Failure`
 
 Exception raised to signal that the given arguments do not make sense. This
-exception take a string as argument.
+exception takes a string as an argument.
 
 
 <CodeTab labels={["ReScript", "JS Output"]}>