Install pkg-config in Debian/Ubuntu containers

It is needed to proper detect the grcc full path
diff --git a/tests/dockerfiles/Kali.docker b/tests/dockerfiles/Kali.docker
index 5442f33..3cb3257 100644
--- a/tests/dockerfiles/Kali.docker
+++ b/tests/dockerfiles/Kali.docker
@@ -5,6 +5,7 @@
     cmake \
     autoconf \
     libtool \
+    pkg-config \
     build-essential \
     python-docutils \
     libcppunit-dev \