tests: resolve ASan error in ManagementTool tests

resolve unused lambda capture errors in newer versions of clang

Change-Id: If03c0a8387ddc35f9999dfbdd3ba474e4387b01b
diff --git a/src/daemon/name-server.cpp b/src/daemon/name-server.cpp
index cc1c881..3e0c2b6 100644
--- a/src/daemon/name-server.cpp
+++ b/src/daemon/name-server.cpp
@@ -133,7 +133,7 @@
     }
     m_validator.validate(*data,
                          bind(&NameServer::doUpdate, this, interest.shared_from_this(), data),
-                         [this] (const Data& data, const security::v2::ValidationError& msg) {
+                         [] (const Data& data, const security::v2::ValidationError& msg) {
                            NDNS_LOG_WARN("Ignoring update that did not pass the verification. "
                                          << "Check the root certificate");
                          });