testing: Reduce runtime of all tests that use SQLite databases by storing them in ramfs

testing/tests/ikev2/ip-split-pools-db/hosts/moon/etc/strongswan.conf

@@ -7,7 +7,7 @@ charon {
 libhydra {
   plugins {
     attr-sql {
-      database = sqlite:///etc/ipsec.d/ipsec.db
+      database = sqlite:///etc/db.d/ipsec.db
     }
   }
 }