Tests: Switch to Fedora-25 for packaging tests
Tests: Switch to Fedora-25 for packaging tests

Switch the Fedora Vagrant box for packaging tests to Fedora-25 as
Fedora-24 will become EOL one month after Fedora-26 is out.

Relates #24466 
strapdata/elassandra5-rc,strapdata/elassandra5-rc,strapdata/elassandra5-rc,strapdata/elassandra5-rc,strapdata/elassandra5-rc