add nullable so intellij doesnt complain

Author: Blast-MC

parchment-api/paper-patches/files/src/main/java/io/papermc/paper/event/player/PlayerPickItemEvent.java.patch

@@ -35,11 +35,11 @@
          this.sourceSlot = sourceSlot;
 +    }
 +
-+    public Location getLocation() {
++    public @org.jetbrains.annotations.Nullable Location getLocation() {
 +        return location;
 +    }
 +
-+    public Entity getEntity() {
++    public @org.jetbrains.annotations.Nullable Entity getEntity() {
 +        return entity;
      }