[KOTLIN][SPRING] fix - properly escape dollar and double quotes

[Picazsoo]

This PR fixes many identified issues with improper escaping of dollar symbol in open api spec. In kotlin, $ has a special meaning in strings and thus needs to be properly escaped by prepending it with backslash \$. In multi-line kotlin strings, the escaping is done by transforming $ into ${'$'}. This merge request fixes the issue everywhere to make compilation possible.

I also unified look and setup of kotlin spring tests where possible. I removed a lot of code repetition and although I am still not super happy with it, the unified structure should make future refactoring a bit easier I presume.

I also checked and fixed any places I could identify where a duplicate escaping of special chars occurred or was simply not needed in the first place.

I fixed all of these (and their {{{.}}} variants):

{{{defaultValue}}}
{{{baseName}}}
{{{path}}}
{{{description}}}
{{{summary}}}
{{{notes}}}
{{{message}}}

I partially covered the fixes by unit tests and partially by introducing new generated samples (and adding the to the compile check pipeline) and by adjusting existing samples to include the potentially problematic strings (param names, descriptions, default values, etc)

For code review of the changed kotlin spring tests I strongly encourage the github setting of ignoring whitespace differences.

PR checklist

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