Due to compatibility break by the recent PostgreSQL core code changes
we need to split expected files into each minor releases rather than
each major releases.
Now the mapping between PostgreSQL version and expected file is
complicated as follows.
* version 10
* >= 10.3 : repack_3.out, tablespace_2.out
* < 10.3 : repack_2.out, tablespace.out
* version 9.6
* >= 9.6.8 : repack_4.out, tablespace_2.out
* < 9.6.8 : repack.out, tablespace.out
* version 9.5
* >= 9.5.12 : repack_4.out, tablespace_2.out
* < 9.5.12 : repack.out, tablespace_1.out
* version 9.4
* >= 9.4.17 : repack_5.out, tablespace_2.out
* < 9.4.17 : repack_1.out, tablespace_1.out
* version 9.3
* >= 9.3.22 : repack_6.out, tablespace_3.out
* < 9.3.22 : repack_1.out, tablespace_1.out
* version 9.2 : repack_1.out, tablespace_1.out
* version 9.1 : repack_1.out, tablespace_1.out
