Test suite: don't use fragile shell construct mixing string and array

The previous code happened to work only because we always pass either 0 or 1
arguments to these functions. If we ever passed them 2+ arguments,
unexpected things would happen.

For details, see https://www.shellcheck.net/wiki/SC2145

tests/regression/apparmor/dbus.inc

@@ -14,7 +14,7 @@ ${__dbus_var_decl}
 $test {
   @{gen $test}
   unix,
-  $@
+  $*
   signal receive peer=unconfined,
 }
 EOF

tests/regression/apparmor/dbus_message.sh

@@ -33,7 +33,7 @@ confined_args="--log=$confined_log $listnames"
 message_gendbusprofile()
 {
 	gendbusprofile "${confined_log} w,
-  $@"
+  $*"
 }
 
 start_bus

tests/regression/apparmor/dbus_service.sh

@@ -62,7 +62,7 @@ service_runchecktest()
 service_gendbusprofile()
 {
 	gendbusprofile "$unconfined_log w,
-  $@"
+  $*"
 }
 
 start_bus

tests/regression/apparmor/dbus_unrequested_reply.sh

@@ -63,7 +63,7 @@ ur_gendbusprofile()
 {
 	gendbusprofile "$confined_log w,
   dbus bind bus=$bus name=$dest,
-  $@"
+  $*"
 }
 
 start_bus