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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master

Details
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http://git.postgresql.org/pg/commitdiff/67eb3e5075b52bb9d91dc3bd9358ac1da2ded5fc

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