chore(doc-gen): fix script paths in plnkr for examples with deps

[gkalpak]

What kind of change does this PR introduce? (Bug fix, feature, docs update, ...)
Chore.

What is the current behavior? (You can also link to an open issue here)
Docs examples with deps result into broken plnkrs due to incorrect script paths (for the production deployment mode).
E.g. <example ... deps="angular-animate.js"> results in:

<script src="//code.angularjs.org/snapshotangular-animate.min.js"></script>

What is the new behavior (if this is a feature change)?
Correct script paths in plnkrs for examples with deps.

Does this PR introduce a breaking change?
No.

Please check if the PR fulfills these requirements

• The commit message follows our guidelines: https://github.com/angular/angular.js/blob/master/CONTRIBUTING.md#commit-message-format
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

Other information
You can see it in action is the examples here (which depend on ngAnimate).