pgsql: tests: Consistently use pg_basebackup -cfast --no-sync to accele

tests: Consistently use pg_basebackup -cfast --no-sync to accelerate tests.

Most tests invoking pg_basebackup themselves did not yet use -cfast, which
makes pg_basebackup take considerably longer. The only reason this didn't
cause the tests to take many minutes is that spread checkpoints only throttle
when writing out a buffer and there aren't that many dirty buffers in the
tests...

Discussion: https://postgr.es/m/20220117195711.xx4qbxutrrlmo2dg@alap3.anarazel.de

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/839f9636b374d67952fdb2b048f055393bc5a8f4

Modified Files
--------------
src/bin/pg_basebackup/t/010_pg_basebackup.pl | 104 ++++++++++++++-------------
src/bin/pg_verifybackup/t/002_algorithm.pl   |   2 +-
src/bin/pg_verifybackup/t/003_corruption.pl  |   2 +-
src/bin/pg_verifybackup/t/004_options.pl     |   2 +-
src/bin/pg_verifybackup/t/006_encoding.pl    |   2 +-
src/bin/pg_verifybackup/t/007_wal.pl         |   4 +-
6 files changed, 61 insertions(+), 55 deletions(-)