pgsql: createdb: Fix quoting of --encoding, --lc-ctype and --lc-collate

createdb: Fix quoting of --encoding, --lc-ctype and --lc-collate

The original coding failed to properly quote those arguments, leading to
failures when using quotes in the values used.  As the quoting can be
encoding-sensitive, the connection to the backend needs to be taken
before applying the correct quoting.

Author: Michael Paquier
Reviewed-by: Daniel Gustafsson
Discussion: https://postgr.es/m/20200214041004.GB1998@paquier.xyz
Backpatch-through: 9.5

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/008cf040962c98c7c55d54c28dcb43c3c1d83c92

Modified Files
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src/bin/scripts/createdb.c        | 29 +++++++++++++++++++----------
src/bin/scripts/t/020_createdb.pl | 26 +++++++++++++++++++++++++-
2 files changed, 44 insertions(+), 11 deletions(-)