fix my grammatical mistakes

Co-authored-by: Felix Arntz <[email protected]>

Author: JasonTheAdams

CONTRIBUTING.md

@@ -12,11 +12,11 @@ All parameters, return values, and properties must use explicit type hints, exce
 
 The following naming conventions must be followed for consistency and autoloading:
 
-- Interfaces are suffixed with `Interface`
-- Traits are suffixed with `Trait`
-- Enums are suffixed with `Enum`
-- File names are the same as the class, trait, and interface name for PSR-4 autoloading
-- Classes, interfaces, and traits, and namespaces must not be prefixed with `Ai`, exluding the root namespace.
+- Interfaces are suffixed with `Interface`.
+- Traits are suffixed with `Trait`.
+- Enums are suffixed with `Enum`.
+- File names are the same as the class, trait, and interface name for PSR-4 autoloading.
+- Classes, interfaces, and traits, and namespaces are not prefixed with `Ai`, exluding the root namespace.
 
 ## PHP Compatibility