Remove incidental md5() function use from test
To allow test to pass in OpenSSL FIPS mode, similar to
657f5f223e, for
a new test that has been added since.
Reviewed-by: Tomas Vondra <tomas@vondra.me>
Discussion: https://www.postgresql.org/message-id/
86763810-70a1-4872-8ba7-
1676f788e5a2@eisentraut.org