tests/qtest: remove break after g_assert_not_reached()

This patch is part of a series that moves towards a consistent use of
g_assert_not_reached() rather than an ad hoc mix of different
assertion mechanisms.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Message-ID: <20240912073921.453203-36-pierrick.bouvier@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>

tests/qtest/migration-helpers.c

@@ -76,7 +76,6 @@ static QDict *SocketAddress_to_qdict(SocketAddress *addr)
         break;
     default:
         g_assert_not_reached();
-        break;
     }
 
     return dict;