Thread: pgsql: Fix outdated bit in README.tuplock

Fix outdated bit in README.tuplock

Apparently this information has been outdated since first committed,
because we adopted a different implementation during development per
reviews and this detail was not updated in the README.

This has been wrong since commit 0ac5ad5134f2 introduced the file in
2013.  Backpatch to all live branches.

Reported-by: Will Mortensen <will@extrahop.com>
Discussion: https://postgr.es/m/CAMpnoC6yEQ=c0Rdq-J7uRedrP7Zo9UMp6VZyP23QMT68n06cvA@mail.gmail.com

Branch
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REL_16_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/aca1599d694d672d65d4f9d2f8378bb93de14c7b

Modified Files
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src/backend/access/heap/README.tuplock | 9 ++-------
1 file changed, 2 insertions(+), 7 deletions(-)