[Kotlin] Fix default value for kotlin class

[Fs02]

• Fix possible typo on kotlin defaultValue in mustache template which cause default value not generated
• Validated on different project by overriding data_class_opt_var.mustache

PR checklist

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• Pull Request title clearly describes the work in the pull request and Pull Request description provides details about how to validate the work. Missing information here may result in delayed response from the community.
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  ./mvnw clean package 
  ./bin/generate-samples.sh
  ./bin/utils/export_docs_generators.sh
  

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cc: @jimschubert @dr4ke616 @karismann @Zomzog @andrewemery @4brunu @yutaka0m

[4brunu]

Hey, first of all, thanks for your PR.
Looks good to me.
Did you validated that you corrected all the places?
Thanks

[Fs02]

Hey, first of all, thanks for your PR.
Looks good to me.
Did you validated that you corrected all the places?
Thanks

Should be, I'm using case sensitive search to find {{defaultvalue}} in my editor
Thanks

[4brunu]

Nice, thanks, let's wait for the CI 👍

[4brunu]

Looks like the sample projects are not updated.
Could you please also fix those.

And then run and commit the changes produced by those commands?

./mvnw clean package 
./bin/generate-samples.sh
./bin/utils/export_docs_generators.sh

[Fs02]

is that search from master branch?

looks like I missed one file, updated here: eaf93dc
Thanks

[4brunu]

Yes it was.
Thanks for the fix.
Let's wait for CI.

[4brunu]

Looks good to me, CI failures doesn't seems to be related to this PR.