[BUG][KOTLIN] Fix the path variable escaping in kotlin client generators

[CaptainAye]

Pr aims to fix an issue when path variable was incorrectly escaped during generation of kotlin client apis. It led to the situation where single quotes were escaped, resulting in invalid code being generated.
Fixes #19930

Technical Kotlin Committee:
@dr4ke616 @karismann @Zomzog @andrewemery @4brunu @yutaka0m @stefankoppier @e5l

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[wing328]

lgtm. thanks for the fix

[wing328]

FYI. I've filed a follow-up PR (#19938) to clean up other templates with similar issues.

Thanks again for contributing the fix.

When you've time, can you please PM me via Slack?

https://join.slack.com/t/openapi-generator/shared_invite/zt-12jxxd7p2-XUeQM~4pzsU9x~eGLQqX2g