Fix Chat meta type

Fixes #1949

common/src/main/java/us/myles/ViaVersion/api/minecraft/metadata/types/MetaType1_12.java

@@ -8,7 +8,7 @@ public enum MetaType1_12 implements MetaType {
     VarInt(1, Type.VAR_INT),
     Float(2, Type.FLOAT),
     String(3, Type.STRING),
-    Chat(4, Type.STRING),
+    Chat(4, Type.COMPONENT),
     Slot(5, Type.ITEM),
     Boolean(6, Type.BOOLEAN),
     Vector3F(7, Type.ROTATION),

common/src/main/java/us/myles/ViaVersion/api/minecraft/metadata/types/MetaType1_9.java

@@ -8,7 +8,7 @@ public enum MetaType1_9 implements MetaType {
     VarInt(1, Type.VAR_INT),
     Float(2, Type.FLOAT),
     String(3, Type.STRING),
-    Chat(4, Type.STRING),
+    Chat(4, Type.COMPONENT),
     Slot(5, Type.ITEM),
     Boolean(6, Type.BOOLEAN),
     Vector3F(7, Type.ROTATION),

common/src/main/java/us/myles/ViaVersion/protocols/protocol1_9to1_8/metadata/MetadataRewriter1_9To1_8.java

@@ -121,7 +121,7 @@ public class MetadataRewriter1_9To1_8 extends MetadataRewriter {
                 metadata.setValue(angle);
                 break;
             case Chat:
-                value = Protocol1_9To1_8.fixJson((String) value);
+                value = Protocol1_9To1_8.fixJson(value.toString());
                 metadata.setValue(value);
                 break;
             default: