Remove CFP dates from devfest-modena-2025.md

Author: Davmuz

_conferences/devfest-modena-2025.md

@@ -5,7 +5,5 @@ location: Modena, Italy
 online: false
 date_start: 2025-10-04
 date_end:   2025-10-05
-cfp_start: 2025-08-01
-cfp_end:   2025-09-20
 cfp_site:  https://sessionize.com/devfest-modena-2025
 ---