pgsql: Disable temporarily TAP tests for contrib/bloom/

Disable temporarily TAP tests for contrib/bloom/

The recent commit 03faa4a8 has enabled those tests, however several
buildfarm members are complaining about their stability on Windows and
macOS. This will keep the buildfarm green, while investigating the
root problem.

Discussion: /messages/by-id/20181126003351.GE1776@paquier.xyz

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/b0b1f4183aa416d30afe35c5bef83d3e21f9b574

Modified Files
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contrib/bloom/Makefile | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)