pgsql: ci: Add 32bit build and test

ci: Add 32bit build and test

It's easy enough to make changes that break on 32bit platforms and few people
test that locally. Add a test for that to CI. LLVM is disabled on 32bit
because installing it would bloat the image size further.

The debian w/ meson task is fast enough that we can afford to test both.

Use the occasion of a separate run of the tests to run them under LANG=C,
we've recently discovered there's not a lot of testing in the buildfarm for
the case.

Discussion: https://postgr.es/m/4033181.1664395633@sss.pgh.pa.us

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/ccf36ea2580f66abbc37f27d8c296861ffaad9bf

Modified Files
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.cirrus.yml | 41 +++++++++++++++++++++++++++++++++++++----
1 file changed, 37 insertions(+), 4 deletions(-)