fix(c): Remove duplicate code generation for UUID path parameters

[BiekerUdan]

The C generator was generating duplicate path parameter handling code when a parameter had format: uuid. This occurred because UUID parameters have both isString=true and isUuid=true flags set, causing both the {{#isString}} and {{#isUuid}} template blocks to execute.

The duplicate {{#isUuid}} block has been removed since it generated identical code to the {{#isString}} block. This makes UUID parameters consistent with email parameters, which already work this way (isEmail=true and isString=true, but only use the {{#isString}} block).

The generated code now compiles successfully without duplicate variable declarations.

Fixes #17448

@zhemant @ityuhui @michelealbano @eafer

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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

[eafer]

Do you mind adding a test for your change to the petstore.yaml for C? So that it doesn't break again in the future.

[BiekerUdan]

I fixed the attribution issue. And added '/pet/byUuid/{uuid}' to petstore.yaml and generated the samples.

This causes builds of the samples to fail before this PR is applied, and to pass after it is applied. I did not add any unit tests specifically for this, is that ok?

[eafer]

Yes, that's what I meant: just put something in place so that the sample build fails if we ever revert this by mistake. Thanks! Your changes look good to me, but I don't think all of the samples got refreshed for some reason.