pgsql: Make PostgreSQL::Test::Cluster::config_data more flexible

Make PostgreSQL::Test::Cluster::config_data more flexible

Currently this only allows for one argument, which must be present, and
always returns a single string. With this change the following now all
work:

$all_config = $node->config_data;
%config_map = ($node->config_data);
$incdir = $node->config_data('--include-dir');
($incdir, $sharedir) = $node->config_data(
qw(--include-dir --share-dir));

Backpatch to release 15 where this was introduced.

Discussion: https://postgr.es/m/73eea68e-3b6f-5f63-6024-25ed26b52016@dunslane.net

Reviewed by Tom Lane, Alvaro Herrera, Michael Paquier.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/a688c39e1dca56490527ccac13ea4ac752c7116a

Modified Files
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src/test/perl/PostgreSQL/Test/Cluster.pm | 43 ++++++++++++++++++++++++++------
1 file changed, 35 insertions(+), 8 deletions(-)