Added a few more known filenames to the list in nginx config

Signed-off-by: Ole Herman Schumacher Elgesem <ole.elgesem@northern.tech>

nginx.conf

@@ -50,7 +50,7 @@ http {
         # deny running scripts inside user folder
         location ~* /user/.*\.(txt|md|yaml|php|pl|py|cgi|twig|sh|bat)$ { return 404; }
         # deny access to specific files in the root folder
-        location ~ /(LICENSE.txt|composer.lock|composer.json|nginx.conf|web.config|htaccess.txt|\.htaccess|package.json|package-lock.json) { return 404; }
+        location ~ /(LICENSE.txt|composer.lock|composer.json|nginx.conf|web.config|htaccess.txt|\.htaccess|package.json|package-lock.json|Dockerfile|Containerfile|Makefile) { return 404; }
         ## End - Security
 
         # Try to keep the file uplodas in the memory: