Add required for maven central publishing #1605

Job	Run time
build (mysql-plugin)	1h 18m 14s
build (oracle-plugin)	2h 31m 2s
build (mssql-plugin)	1h 40m 52s
build (cloudsql-mysql-plugin)	1h 54m 35s
build (cloudsql-postgresql-plugin)	52m 30s
build (postgresql-plugin)	50m 24s
	9h 7m 37s

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