Broken and rotten TAP tests in contrib/bloom/

Hi Alexander & Teodor,

It happens that the buildfarm machines do not like much the set of TAP
tests present in contrib/bloom/:
https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=longfin&dt=2018-11-25%2023%3A59%3A03

Here is an extract of the failure:
#   Failed test 'initial: query result matches'
#   at t/001_wal.pl line 38.
#          got: '0|d
# 0|9
# 0|3
# 0|d

These currently cannot run within the buildfarm as a custom Makefile
target is used.  And likely many developers don't run them either.

Could you look at what is wrong in them?  Thanks,
--
Michael