fix: rest matcher skipped if optional is empty

[pzerelles]

I found that since version 1.3.6 a matcher on a rest parameter is not called anymore if an optional parameter before it is empty. I'm using the optional for localization and the following rest parameter has a matcher.

Example route:
[[locale=locale]]/[...rest=page]

For /en/test, the page matcher will be called with param test.
For /test, the page matcher was not called since version 1.3.6.

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[elliott-with-the-longest-name-on-github]

Pretty sure this more comprehensive PR fixes this issue as well: #9987

[elliott-with-the-longest-name-on-github]

Hmm, maybe not -- not sure -- either way, let's not add integration tests for this. There's a routing.spec.ts file with unit tests for exec that you can use to test this behavior. It runs much faster than integration tests and I don't think we get any meaningfully better coverage by using integration tests in this case!

[pzerelles]

Changed integration test to unit test. I'm pretty sure that #9987 does not fix that case.

[benmccann]

@pzerelles would you mind addressing the merge conflict that's shown up? It's a result of me merging #9987

[benmccann]

Pretty sure this more comprehensive PR fixes this issue as well: #9987

The unit test here fails without the change that's here, so I'm going to say this change is still necessary and go ahead and merge it.

I cut a release with #9987 in it so that the two PRs will be in separate releases. That way if anyone encounters any regressions related to routing changes it will be easier to tell which PR affected it