Fixed incomplete redo of brittle charcoal adventure fix

(had reverted after improper testing with axe instead of shovel, then
neglected to check rebuilding with gradle after re-implementing fix in
source)

src/main/java/gregtech/common/blocks/GT_Material_Reinforced.java

@@ -5,7 +5,7 @@ import net.minecraft.block.material.Material;
 
 public class GT_Material_Reinforced
         extends Material {
-    public GT_Material_Machines() {
+    public GT_Material_Reinforced() {
         super(MapColor.stoneColor);
         setRequiresTool();
         setAdventureModeExempt();