pgsql: Simplify TAP tests of pg_dump for connection strings

Simplify TAP tests of pg_dump for connection strings

The last set of scenarios did an initialization of nodes followed by an
extra command to set up the authentication policy with pg_regress
--config-auth.  This configuration step can be integrated directly using
the option auth_extra from PostgresNode::init when initializing the
node, saving from one extra command.  On Windows, this also restricts
more pg_ident.conf for the SSPI user mapping by removing the entry of
the OS user running the test, which is not needed anyway.

Note that IPC::Run mishandles double quotes, hence the restore user name
is changed to map with that.  This was already done in the test as a
later step, but not in a consistent way, causing the switch to use
auth_extra to fail.

Found while reviewing ca129e5.

Discussion: https://postgr.es/m/20190703062024.GD3084@paquier.xyz

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/d5ab9a891cb590aad4278026b2edda685f2524a2

Modified Files
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src/bin/pg_dump/t/010_dump_connstr.pl | 32 ++++++++++++--------------------
1 file changed, 12 insertions(+), 20 deletions(-)