pgsql: Revert "Fix isolation test to be less timing-dependent"

Revert "Fix isolation test to be less timing-dependent"

This reverts commit 2268e6afd596. It turned out that inconsistency in
the report is still possible, so go back to the simpler formulation of
the test and instead add an alternate expected output.

Discussion: https://postgr.es/m/20180103193728.ysqpcp2xjnqpiep7@alvherre.pgsql

Branch
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REL9_6_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/b64d6c9341522e89f30beecc72ce8859afd8b6c9

Modified Files
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src/test/isolation/expected/multiple-cic.out | 15 +++++----------
src/test/isolation/expected/multiple-cic_1.out | 20 ++++++++++++++++++++
src/test/isolation/specs/multiple-cic.spec | 12 ++++--------
3 files changed, 29 insertions(+), 18 deletions(-)