Improve directory name extraction from branch name.

[dreid]

Fixes #493 Fixes #494

This improves directory extraction to handle two previously unhandled cases:

1. a multi-segment directory with a non-standard separator is now properly reconstructed by joining on /
2. the - included in the depname-version portion is properly accounted for when the delimiter is -.

I did not address the fact that the existing non-standard separator test uses a separator (|) that does not appear to be valid according to the dependabot documention.

[jeffwidman]

👋 thanks for this! I'm on paternity leave right now so hesitant to merge this until I return, as I don't want to risk any problems that others would have to cleanup... but when I return in June I plan to take a look at this and hopefully ship it.

[Nishnha]

There are some merge conflicts that you will need to resolve by rebasing/merging and re-running the build script before I can merge this

[dreid]

@Nishnha These cases appear to be covered by the refactoring of directory detection that landed in https://github.com/dependabot/fetch-metadata/commit/a44a9dfd95f38ab057ce5d8277f31e18ba4a86b6

[sachin-sandhu]

Hi @dreid , Can you please resolve the merge conflicts so that we may proceed to complete the code merge.

Conflicting files dist/index.js src/dependabot/update_metadata.ts

[dreid]

I believe these underlying issues were already fixed by https://github.com/dependabot/fetch-metadata/commit/a44a9dfd95f38ab057ce5d8277f31e18ba4a86b6