pgsql: Fix memory leaks in error reporting with LOG level

Fix memory leaks in error reporting with LOG level

When loglevel is set to LOG, allocated strings used in the error
message would leak. Fix by explicitly pfreeing them.

Author: Ranier Vilela <ranier.vf@gmail.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/CAEudQAqMeE0AHcOsOzZx51Z0eiFJAjhBPRFt+Bxi3ETXWen7ig@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/b362d14816699ed05c47355dcb20bbe46f350b86

Modified Files
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src/backend/archive/shell_archive.c  | 2 ++
src/backend/libpq/be-secure-common.c | 6 +++++-
2 files changed, 7 insertions(+), 1 deletion(-)