pgsql: Use carriage returns for data insertion logs in pgbench on termi

Use carriage returns for data insertion logs in pgbench on terminal

This is similar to what pg_basebackup and pg_rewind do when reporting
cumulative data, and that's more user-friendly.  Carriage returns are
now used when stderr points to a terminal, and newlines are used in
other cases, like a redirection to a log file.

Author: Amit Langote
Reviewed-by: Fabien Coelho
Discussion: https://postgr.es/m/CA+HiwqFNwEjPeVaQsp2L7DyCPv1Eg1guwhrVhzMYqUJUk8ULKg@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/d37ddb745be07502814635585cbf935363c8a33d

Modified Files
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src/bin/pgbench/pgbench.c | 16 +++++++++++-----
1 file changed, 11 insertions(+), 5 deletions(-)