[TECH] Ajouter le dossier de migrations aux codeowners (#11596)

Author: yannbertrand

.github/CODEOWNERS

@@ -60,5 +60,6 @@
 /admin/app/services/oidc-identity-providers.js @1024pix/team-acces
 /admin/app/services/session.js @1024pix/team-acces
 
-
+# Directories maintainted by team Captains
+/api/db/migrations/ @1024pix/team-captains