refactor: make GameLogic.checkRequest use error pattern and simple check methods

src/main/java/uulm/teamname/marvelous/gamelibrary/entities/StatType.java

@@ -6,6 +6,6 @@ public enum StatType {
     HP,
     /** Represents the movement points of a character */
     MP,
-    /** Represents thr action points of a character */
+    /** Represents the action points of a character */
     AP
 }