app_python3: Makefile - suppress warning if --embed is not supported by python3-config

(cherry picked from commit 392688fc756a97f65c2433bb6af7adedca4e0abf)

src/modules/app_python3/Makefile

@@ -12,7 +12,7 @@ NAME=app_python3.so
 PYTHON3?=python3
 
 LIBS=${shell \
-	tmp_py3_libs=$$(${PYTHON3}-config --ldflags --embed) || \
+	tmp_py3_libs=$$(${PYTHON3}-config --ldflags --embed 2>/dev/null) || \
 	tmp_py3_libs=$$(${PYTHON3}-config --ldflags); \
 	echo $$tmp_py3_libs}