Thread: pgsql: Fix outdated bit in README.tuplock

Fix outdated bit in README.tuplock

Apparently this information has been outdated since first committed,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_17_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/e2b08a6295826a0dd8ee905e9f8d2c8940fca049

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