Add gnupg2 to combo dependencies

dockerfile/Dockerfile

@@ -13,7 +13,7 @@ ARG APT_REPO="release"
 
 RUN DEBIAN_FRONTEND='noninteractive'                     && \
     apt-get update                                       && \
-    apt-get install -y sudo wget vim locales git   && \
+    apt-get install -y sudo wget vim locales git gnupg2  && \
     apt-get clean
 
 # This is the brute-force solution for Debian;