[FLINK-20841][git] Remove .gitignore entries for generated files

Author: XComp

.gitignore

@@ -19,9 +19,6 @@ tmp
 *.pyc
 .DS_Store
 build-target
-flink-end-to-end-tests/flink-datastream-allround-test/src/main/java/org/apache/flink/streaming/tests/avro/
-flink-formats/flink-avro/src/test/java/org/apache/flink/formats/avro/generated/
-flink-formats/flink-parquet/src/test/java/org/apache/flink/formats/parquet/generated/
 flink-runtime-web/web-dashboard/node/
 flink-runtime-web/web-dashboard/node_modules/
 flink-runtime-web/web-dashboard/web/