update konnect (#299)

* update konnect to 0.28.0
* make signing_method configurable
* instruct npm to run with unsafe permissions (fixes error on jenkins)
  * https://github.com/npm/npm/issues/20861

konnect/Dockerfile

@@ -1,4 +1,4 @@
-ARG CODE_VERSION=0.26.0
+ARG CODE_VERSION=0.28.0
 FROM kopano/konnectd:${CODE_VERSION}
 
 ARG VCS_REF

konnect/wrapper.sh

@@ -122,6 +122,11 @@ if [ -n "${uri_base_path:-}" ]; then
 	set -- "$@" --uri-base-path="$uri_base_path"
 fi
 
+if [ -n "${signing_method:-}" ]; then
+	echo "Entrypoint: Setting signing_method to $signing_method"
+	set -- "$@" --signing-method="$signing_method"
+fi
+
 if [ "${insecure:-}" = "yes" ]; then
 	echo "Entrypoint: running Konnect in insecure mode"
 	set -- "$@" "--insecure"