Fix Spigot annotation mistakes

while some of these may of been true, they are extreme cases and cause
a ton of noise to plugin developers.

Use ApiStatus.Internal instead of Deprecated for actual internal API
that continues to have use (internally).

These do not help plugin developers if they bring moise noise than value.

paper-api/src/main/java/org/bukkit/entity/Minecart.java

@@ -102,7 +102,9 @@ public interface Minecart extends Vehicle {
      * Passing a null value will set the minecart to have no display block.
      *
      * @param material the material to set as display block.
+     * @deprecated use {@link #setDisplayBlockData(BlockData)}
      */
+    @Deprecated(forRemoval = true, since = "1.13")
     public void setDisplayBlock(@Nullable MaterialData material);
 
     /**
@@ -110,8 +112,10 @@ public interface Minecart extends Vehicle {
      * This function will return the type AIR if none is set.
      *
      * @return the block displayed by this minecart.
+     * @deprecated use {@link #getDisplayBlockData()}
      */
     @NotNull
+    @Deprecated(forRemoval = true, since = "1.13")
     public MaterialData getDisplayBlock();
 
     /**