Deprecate BlockType#isInteractable (#11427)

While BlockType is still marked as internal, it mirrors the already
paper-deprecated method #isInteractable.

The commit marks said method as deprecated if/when BlockType becomes
experimental/non-internal.

patches/api/0166-Fix-Spigot-annotation-mistakes.patch

@@ -713,6 +713,25 @@ index 3e07fc1bc0e08d0cfd998711c7fd547b2b7b6b73..f4a739d8022d19a7ae0ee9bf93eb5c48
 +    @Deprecated(forRemoval = true, since = "1.13")
      void setData(@NotNull MaterialData data);
  
+     /**
+diff --git a/src/main/java/org/bukkit/block/BlockType.java b/src/main/java/org/bukkit/block/BlockType.java
+index dfd8187ef941e8afe9cb28a26bf0d2cf2e4c4bc5..d285a1df492d2155f179e8abc17d0bf7527e6d38 100644
+--- a/src/main/java/org/bukkit/block/BlockType.java
++++ b/src/main/java/org/bukkit/block/BlockType.java
+@@ -3433,9 +3433,14 @@ public interface BlockType extends Keyed, Translatable {
+      * state as well. This method will return true if there is at least one
+      * state in which additional interact handling is performed for the
+      * block type.
++     * 
++     * @deprecated This method is not comprehensive and does not accurately reflect what block types are
++     * interactable. Many "interactions" are defined on the item not block, and many are conditional on some other world state
++     * checks being true.
+      *
+      * @return true if this block type can be interacted with.
+      */
++    @Deprecated // Paper
+     boolean isInteractable();
+ 
      /**
 diff --git a/src/main/java/org/bukkit/block/BrushableBlock.java b/src/main/java/org/bukkit/block/BrushableBlock.java
 index 4bd127b3646307398e0c937c3e36ab671235b72b..f2557a87f468ee20c2d276dbfc0e9a976656c75c 100644