Remove param tag for non-existent parameter in ObjectSerializer

[szepeviktor]

@phpstan discovered this param tag.

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• Read the contribution guidelines.
• 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.
• Run the following to build the project and update samples:

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

  (For Windows users, please run the script in Git BASH)
  Commit all changed files.
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[wing328]

please follow step 3 to update the samples so that the CI can verify the change.

[szepeviktor]

Thank you.

I do not have Java environment on my linux instance.
But I have a text editor! ✈️

[szepeviktor]

update the samples

@wing328 Done 🍏

[wing328]

cc @jebentier (2017/07), @dkarlovi (2017/07), @mandrean (2017/08), @jfastnacht (2017/09), @ybelenko (2018/07), @renepardon (2018/12)

[wing328]

tested locally and all tests passed:

 % ./vendor/bin/phpunit tests
PHPUnit 9.6.19 by Sebastian Bergmann and contributors.

...............................................................  63 / 215 ( 29%)
............................................................... 126 / 215 ( 58%)
............................................................... 189 / 215 ( 87%)
..........................                                      215 / 215 (100%)

Time: 00:01.302, Memory: 12.00 MB

[szepeviktor]

Glad to contribute.

[szepeviktor]

Making tools better is a win-win!

[wing328]

Definitely 👍

FYI. We also have a new php-nextgen client generator. Please give it a try to see if it better meets your requirement.