build: make precompiled headers more useful

This can reduce the compilation time of a release
build (without tests) by more than 40%

Refs: #5212
Change-Id: I977aff0c0c7becbfee8a8b55605b81d0c014829b
diff --git a/tests/tools/nfdc/command-definition.t.cpp b/tests/tools/nfdc/command-definition.t.cpp
index 6314e2e..bf1f1a0 100644
--- a/tests/tools/nfdc/command-definition.t.cpp
+++ b/tests/tools/nfdc/command-definition.t.cpp
@@ -28,6 +28,8 @@
 
 #include "tests/test-common.hpp"
 
+#include <boost/lexical_cast.hpp>
+
 namespace nfd::tools::nfdc::tests {
 
 BOOST_AUTO_TEST_SUITE(Nfdc)