travis: disable windows signing by setting CSC_LINK and CSC_KEY_PASSWORD to empty, attempt 2

jkowalski · jkowalski · commit f9db94ca777e · 2020-02-18T06:50:35.000-08:00
diff --git a/Makefile b/Makefile
@@ -67,8 +67,8 @@ endif
 
 ifeq ($(TRAVIS_OS_NAME),windows)
 # disable Kopia UI code siging.
-CSC_LINK:=
-CSC_KEY_PASSWORD:=
+undefine CSC_LINK
+undefine CSC_KEY_PASSWORD
 endif
 
 kopia-ui: goreleaser
