Use multiple formatters in the same test run

[vearutop]

Resolves #346.

This PR implements formatter that can propagate events to multiple other formatters.
Multiple formatters can be configured as comma-separated list in Options.Format, for example pretty,junit:junit.xml.

[codecov]

Codecov Report

Merging #392 (707025d) into main (60e2e2f) will increase coverage by 0.14%.
The diff coverage is 96.22%.

@@            Coverage Diff             @@
##             main     #392      +/-   ##
==========================================
+ Coverage   81.13%   81.27%   +0.14%     
==========================================
  Files          25       26       +1     
  Lines        1998     2024      +26     
==========================================
+ Hits         1621     1645      +24     
- Misses        274      275       +1     
- Partials      103      104       +1     

Impacted Files	Coverage Δ
internal/formatters/fmt_multi.go	91.66% <91.66%> (ø)
run.go	83.46% <100.00%> (+0.26%)	⬆️

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[voiski]

LGTM! I'm looking forward to have it. Very nice.

[aslakhellesoy]

I'm not very familiar with the Godog codebase (but I am familiar with Go and the Cucumber libraries it builds upon).

The code looks good to me, but it's usually @lonnblad who reviews and merges pull requests in Godog. Let's wait a week or so to see if he has time to review this.

[aslakhellesoy]

This looks good to me, and if you think it's ready to merge I'll do it @vearutop.

We're discussing a merge of godog/gobdd over in the #committers-go channel in the Cucumber slack - any chance you could join the discussion there?

[aslakhellesoy]

Hi @vearutop,

Thanks for your making your first contribution to Cucumber, and welcome to the Cucumber committers team! You can now push directly to this repo and all other repos under the cucumber organization! 🍾

In return for this generous offer we hope you will:

• ✅ Continue to use branches and pull requests. When someone on the core team approves a pull request (yours or someone else's), you're welcome to merge it yourself.
• 💚 Commit to setting a good example by following and upholding our code of conduct in your interactions with other collaborators and users.
• 💬 Join the community Slack channel to meet the rest of the team and make yourself at home.
• ℹ️ Don't feel obliged to help, just do what you can if you have the time and the energy.
• 🙋 Ask if you need anything. We're looking for feedback about how to make the project more welcoming, so please tell us!

On behalf of the Cucumber core team,
Aslak Hellesøy
Creator of Cucumber