pgsql: Remove reference to ftp servers from documentation

Remove reference to ftp servers from documentation

It's been a long time since we used ftp, but there was a single
reference left in the docs.

Author: Daniel Gustafsson <[hidden email]>
Discussion: https://postgr.es/m/6880D602-7286-46EC-8A03-14E3248FEC7A@...

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/0a9ae44288d122c12aa0862b032ae892942da452

Modified Files
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doc/src/sgml/install-windows.sgml | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)