make pickleStepIDs unique accross multiple paths

[rickardenglund]

Ran into trouble with pickleStepID not being unique when having the feature files on multiple paths.

In the failing scenario we have a bunch of features distributed along multiple paths.
I experienced a nil pointer dereference in the pretty printer when executing a scenario outline pickle.
The pickleStep received from pickleStep = f.storage.MustGetPickleStep(result.PickleStepID) was originating from a different feature from a different path

[codecov]

Codecov Report

Merging #366 (c05845a) into master (adfc936) will increase coverage by 1.90%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #366      +/-   ##
==========================================
+ Coverage   79.12%   81.03%   +1.90%     
==========================================
  Files          25       25              
  Lines        1993     1993              
==========================================
+ Hits         1577     1615      +38     
+ Misses        320      275      -45     
- Partials       96      103       +7     

Impacted Files	Coverage Δ
internal/parser/parser.go	60.81% <100.00%> (+51.35%)	⬆️

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[aslakhellesoy]

Hi @rickardenglund,

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