pgsql: Avoid moving data directory in upgrade testing.

Avoid moving data directory in upgrade testing.

Windows sometimes gets upset if we rename a large directory and then try
to use the old name quickly, as seen in occasional buildfarm failures.
So we avoid that by building the old version in the intended
destination in the first place instead of renaming it, similar to the
change made for the same reason in commit b7f8465c.

Branch
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REL9_2_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/4e205ec4d9ef0f75ed39e5e8f0cd338d94c154c5

Modified Files
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contrib/pg_upgrade/test.sh |    7 ++++---
1 files changed, 4 insertions(+), 3 deletions(-)