Add missing license header

fabric-convention-tags-v1/src/datagen/java/net/fabricmc/fabric/impl/tag/convention/datagen/generators/EnglishTagLangGenerator.java

@@ -1,3 +1,19 @@
+/*
+ * Copyright (c) 2016, 2017, 2018, 2019 FabricMC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
 package net.fabricmc.fabric.impl.tag.convention.datagen.generators;
 
 import net.fabricmc.fabric.api.datagen.v1.FabricDataOutput;