rasa data validate stories misses some conflicts with rules

[JEM-Mosig]

Rasa version:
Rasa Version : 2.0.0
Rasa SDK Version : 2.0.0a5
Rasa X Version : 0.32.0
Python Version : 3.7.0 (default, Oct 9 2018, 10:31:47)
Operating System : Linux-4.15.0-118-generic-x86_64-with-debian-buster-sid

Issue:
The rasa data validate stories command misses some conflicts between rules and stories that appear at the beginning of the story. Specifically, if you create a rasa init project and replace rules.yml with

version: "2.0"
rules:
- rule: the rule
  steps:
  - intent: goodbye
  - action: utter_iamabot

and stories.yml with

version: "2.0"
stories:
- story: the story
  steps:
  - intent: goodbye
  - action: utter_goodbye

and then run rasa data validate stories, the output will be No story structure conflicts found, which is wrong.
The conflict is found correctly if you add conversation_start: true to the rule. This is caused by the ... action that comes from the rule and throws off the validation code.

Related discussion on Slack.

Error (including full traceback):

No story structure conflicts found

Command or request that led to error:

rasa data validate stories

[JEM-Mosig]

It is probably best to just not check rules with this tool, as rule also apply in the middle of dialogues and it is hard to square with the story validation. Furthermore, rule consistency with stories is already checked during rasa train core.