pgsql: Fix findoidjoins to recognize oidvector columns.

Fix findoidjoins to recognize oidvector columns.

Somehow we'd never noticed this oversight, even though it means
that such basic columns as pg_proc.proargtypes were not being
validated by the oidjoins test.  Correct the query and update
the test script with the newly-found dependencies.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/96d175e3e2ea1bbf734f21444126a711da12108b

Modified Files
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src/test/regress/expected/oidjoins.out | 40 ++++++++++++++++++++++++++++++++++
src/test/regress/sql/oidjoins.sql      | 20 +++++++++++++++++
src/tools/findoidjoins/README          |  5 +++++
src/tools/findoidjoins/findoidjoins.c  |  2 +-
4 files changed, 66 insertions(+), 1 deletion(-)