pgsql: Use "true" not "TRUE" in one ICU function call.

Use "true" not "TRUE" in one ICU function call.

This was evidently missed in commit 6337865f3, which generally did
s/TRUE/true/ everywhere. It escaped notice up to now because ICU
versions before ICU 68 provided definitions of "TRUE" and "FALSE"
regardless. With ICU 68, it fails to compile.

Per report from Condor. Back-patch to v11 where 6337865f3 came in.
(I've not tested v10, where this call originated, but I imagine
it's fine since we defined TRUE in c.h back then.)

Discussion: https://postgr.es/m/[email protected]

Branch
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REL_12_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/029fa664ecb8687eb60633b4ccf230b457a1fb77

Modified Files
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src/backend/commands/collationcmds.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)