Update Makefile (#480)

Set upload email in makefile in an attempt to avoid future failures uploading to the IETF datatracker due to scrobbling the wrong email

see also oauth-wg/oauth-sd-jwt-vc#255

Author: bc-pi

Makefile

@@ -1,6 +1,8 @@
 LIBDIR := lib
 include $(LIBDIR)/main.mk
 
+export UPLOAD_EMAIL ?= [email protected]
+
 $(LIBDIR)/main.mk:
 ifneq (,$(shell grep "path *= *$(LIBDIR)" .gitmodules 2>/dev/null))
 	git submodule sync