allow check for path parameters in matrix style

[mkresse]

Fixes #16330 by adding a boolean variable isMatrix to mustache parameter context. This allows custom template code like:

{{#isPathParam}}{{#isMatrix}}@MatrixParam{{/isMatrix}}{{^isMatrix}}@PathParam{{/isMatrix}}

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[wing328]

Thanks for the PR but your commit (as shown in the Commits tab) is not linked to your Github account, which means this PR won't count as your contribution in https://github.com/OpenAPITools/openapi-generator/graphs/contributors.

Let me know if you need help fixing it.

Ref: https://github.com/OpenAPITools/openapi-generator/wiki/FAQ#how-can-i-update-commits-that-are-not-linked-to-my-github-account

[wing328]

can you please also add a test or two to cover the new flag?

[mkresse]

@wing328, thanks for your very quick reply. Also thanks for your hint regarding the author - just fixed that with a force push. I also added a simple unit test for the new flag, I hope this is sufficient.

[wing328]

cc @OpenAPITools/generator-core-team