Fix Material#isFlammable not being accounted for in flammability (#10572)

src/main/java/net/minecraftforge/common/extensions/IForgeBlock.java

@@ -607,7 +607,7 @@ public interface IForgeBlock
      */
     default boolean isFlammable(BlockState state, BlockGetter level, BlockPos pos, Direction direction)
     {
-        return state.getFlammability(level, pos, direction) > 0;
+        return state.getMaterial().isFlammable() && state.getFlammability(level, pos, direction) > 0;
     }
 
     /**