pgsql: Don't use Perl pack('Q') in 039_end_of_wal.pl.

Don't use Perl pack('Q') in 039_end_of_wal.pl.

'Q' for 64 bit integers turns out not to work on 32 bit Perl, as
revealed by the build farm.  Use 'II' instead, and deal with endianness.

Back-patch to 12, like bae868ca.

Discussion: https://postgr.es/m/ZQ4r1vHcryBsSi_V%40paquier.xyz

Branch
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REL_16_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/cc58607b019ad6dd3231e54c597e6c1bc07a8132

Modified Files
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src/test/recovery/t/039_end_of_wal.pl | 24 ++++++++++++++++++------
1 file changed, 18 insertions(+), 6 deletions(-)