ci: Use Fedora 41 default flang package now that it is new enough

In commit fff8e3f6f3 (ci: Rebuild Fedora 41 image with updates,
2024-11-11, v3.31.1~20^2) we specified an exact version of the `flang`
package to update beyond the default at the time.  Revert that now that
the default is newer.