Update kexi to version 3.2.0 / rev 11 via SR 902811
    
    https://build.opensuse.org/request/show/902811
    by user cgiboudeaux + dimstar_suse
    - BuildRequire postgresql-server-devel also on Leap 15.2/15.3 to
      fix missing PostgreSQL migration driver
    
    Similar to SR#785407 in kdb, but I decided to omit the %if completely as 15.1 is no longer supported. (forwarded request 902805 from wolfi323)