refactor(env): move SESSIONS_STORAGE to app configuration section

Author: borjapazr

.env

@@ -1,6 +1,7 @@
 ## App configuration ##
 NODE_ENV=development
 PORT=5000
+SESSIONS_STORAGE=cache # cache or db
 LOGS_ENABLED=true
 
 ## App information overrides ##
@@ -16,7 +17,6 @@ APP_NAME=express-typescript-skeleton
 # App configuration #
 IMAGE_NAME=express-typescript-skeleton
 EXTERNAL_PORT=5000
-SESSIONS_STORAGE=cache # cache or db
 LOGS_VOLUME=../.docker/app/logs
 
 # Database configuration #