Render correct graph for non-default events

actions/testdata/multi.workflow

@@ -0,0 +1,19 @@
+workflow "buildwf" {
+  on = "push"
+  resolves = ["build"]
+}
+
+action "build" {
+  uses = "./action1"
+  args = "echo 'build'"
+}
+
+workflow "deploywf" {
+  on = "release"
+  resolves = ["deploy"]
+}
+
+action "deploy" {
+  uses = "./action2"
+  runs = ["/bin/sh", "-c", "cat $GITHUB_EVENT_PATH"]
+}