Fix: Include spell name in default msg for relic spells

[inogenous]

Summary

Bugfixes "Include spell name in default msg for relic spells"

Purpose of change

• Include spell name in You cast: %s! also for relic spell effects
• Prevents unformatted %s shown in message log when activating relic with, for example, AEA_FATIGUE.

Describe the solution

Spell message for relic effects should be formatted same way as done in activity_handlers::spellcasting_finish

Describe alternatives you've considered

• For this particular message (shown in screenshot above), another option would be to provide json message for AEA_FATIGUE in data/json/artifact/legacy_artifact_active.json.

Testing

$ ./tests/cata_test
...
All tests passed (28256659 assertions in 977 test cases)

Additional context