feat(gherkin): add gherkin Background

[amiceli]

This PR is to add Background functionnality. I will implement these rules :

• only one Background for a Feature
• only one Background for a Rule
• allow And and Given steps for a Background
• A warning if a Background contains more than 4 lines (tips read in Gherkin doc)

[NomanChali]

When are you planning to merge this PR?

[amiceli]

I'm still working on it (event if we don't see commit :)) to run background correctly before each scenario (for feature and rule). I can publish a a beta version if you want to test it.

Otherwise I will merge it this week.

[NomanChali]

I'm still working on it (event if we don't see commit :)) to run background correctly before each scenario (for feature and rule). I can publish a a beta version if you want to test it.

Otherwise I will merge it this week.

Thanks for your quick response beta version would be helpful

[amiceli]

Ok, I'm working on a fix for scenario and background call order (with feature and rule). I will publish a beta version ;) I will put a message one this PR.

[amiceli]

@NomanChali I've publish 3.3.0-beta.2 version. You can use Background in feature and rule(s).

I'm still working on it but you can test it. I tried this beta version on some projects, tests still pass ;).

[amiceli]

To give some news. Code is ok, I'm working to improve unit tests for Background feature. And fix cli-generate command, I've error with esm, not esm, commonJs etc ^^.