pgsql: Add PostgresNode::command_fails_like()

Add PostgresNode::command_fails_like()

This is useful to test for a command failure with some default
connection parameters associated to a node, in combination with checks
on error patterns expected. This routine will be used by an upcoming
future patch, but could be also plugged into some of the existing
tests.

Extracted from a larger patch by the same author.

Author: Ronan Dunklau
Discussion: /messages/by-id/5742739.ga3mSNWIix@aivenronan

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/de1d4fef71cb00370aa5f794fe05355c1d063aea

Modified Files
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src/test/perl/PostgresNode.pm | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)