pgsql: pg_bsd_indent: Collect test diffs in test.diffs instead of tests

pg_bsd_indent: Collect test diffs in test.diffs instead of tests.diff

That way CI knows to pick up the file if the test fails.

Discussion: /messages/by-id/20230711233307.hu4wetabjm5f7ver@awork3.anarazel.de
Backpatch: 16-, where the test was added

Branch
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REL_16_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/eeb28a2d94220a8540a57ca8204eaff8cadaf1fa

Modified Files
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src/tools/pg_bsd_indent/t/001_pg_bsd_indent.pl | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)