pgsql: meson: windows: Normalize slashes in prefix

meson: windows: Normalize slashes in prefix

This fixes a build issue on windows, when the prefix is set to a path with
forward slashes. Windows python defaults to a path with a backslash, but mingw
ucrt python defaults to a forward slash. This in turn lead to a wrong PATH set
during tests, causing tests to fail.

Reported-by: Melih Mutlu <m.melihmutlu@gmail.com>
Discussion: http://postgr.es/m/20220928022724.erzuk5v4ai4b53do@awork3.anarazel.de

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/e3a892539b2baabc1963c31605728bbbc8f8b89a

Modified Files
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meson.build | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)