pgsql: Add missing .gitignore for src/test/modules/test_cloexec.

Add missing .gitignore for src/test/modules/test_cloexec.

Branch
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REL_16_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/ebd5696166f6781afb8b4c0b102270059749fad4
Author: Tom Lane <tgl@sss.pgh.pa.us>

Modified Files
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src/test/modules/test_cloexec/.gitignore | 3 +++
1 file changed, 3 insertions(+)