Align Antlr versions used during testing

[INFO] --- antlr4test-maven-plugin:1.11:test (MySql) @ debezium-ddl-parser ---
Parsing :/Users/gmorling/Development/debezium/debezium/debezium-ddl-parser/src/test/resources/mysql/examples/ddl_flush.sql
ANTLR Tool version 4.8 used for code generation does not match the current runtime version 4.7.2ANTLR Runtime version 4.8 used for parser compilation does not match the current runtime version 4.7.2ANTLR Tool version 4.8 used for code generation does not match the current runtime version 4.7.2ANTLR Runtime version 4.8 used for parser compilation does not match the current runtime version 4.7.2Parsing :/Users/gmorling/Development/debezium/debezium/debezium-ddl-parser/src/test/resources/mysql/examples/smoke_tests.sql
ANTLR Tool version 4.8 used for code generation does not match the current runtime version 4.7.2ANTLR Runtime version 4.8 used for parser compilation does not match the current runtime version 4.7.2ANTLR Tool version 4.8 used for code generation does not match the current runtime version 4.7.2ANTLR Runtime version 4.8 used for parser compilation does not match the current runtime version 4.7.2Parsing :/Users/gmorling/Development/debezium/debezium/debezium-ddl-parser/src/test/resources/mysql/examples/ext_tests.sql
ANTLR Tool version 4.8 used for code generation does not match the current runtime version 4.7.2ANTLR Runtime version 4.8 used for parser compilation does not match the current runtime version 4.7.2ANTLR Tool version 4.8 used for code generation does not match the current runtime version 4.7.2ANTLR Runtime version 4.8 used for parser compilation does not match the current runtime version 4.7.2Parsing :/Users/gmorling/Development/debezium/debezium/debezium-ddl-parser/src/test/resources/mysql/examples/dml_delete.sql
ANTLR Tool version 4.8 used for code generation does not match the current runtime version 4.7.2ANTLR Runtime version 4.8 used for parser compilation does not match the current runtime version 4.7.2ANTLR Tool version 4.8 used for code generation does not match the current runtime version 4.7.2ANTLR Runtime version 4.8 used for parser compilation does not match the current runtime version 4.7.2Parsing :/Users/gmorling/Development/debezium/debezium/debezium-ddl-parser/src/test/resources/mysql/examples/optimize.sql
ANTLR Tool version 4.8 used for code generation does not match the current runtime version 4.7.2ANTLR Runtime version 4.8 used for parser compilation does not match the current runtime version 4.7.2ANTLR Tool version 4.8 used for code generation does not match the current runtime version 4.7.2ANTLR Runtime version 4.8 used for parser compilation does not match the current runtime version 4.7.2Parsing :/Users/gmorling/Development/debezium/debezium/debezium-ddl-parser/src/test/resources/mysql/examples/dml_select.sql

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