pgsql: postgres_fdw: Remove useless ternary expression.

postgres_fdw: Remove useless ternary expression.

There is no case where we would call pgfdw_exec_cleanup_query or
pgfdw_exec_cleanup_query_{begin,end} with a NULL query string, so this
expression is pointless; remove it and instead add to the latter
functions an assertion ensuring the given query string is not NULL.

Thinko in commit 815d61fcd.

Discussion: https://postgr.es/m/CAPmGK14mm%2B%3DUjyjoWj_Hu7c%2BQqX-058RFfF%2BqOkcMZ_Nj52v-A%40mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/dd24098cd6fdd599dcee0cd379bb8bdb0c3710a4

Modified Files
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contrib/postgres_fdw/connection.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)