PHP 8.0 compatibility

Problem/Motivation

I am trying to check for errors via phpcs and PHPCompatibility standard on a drupal project, here is the command:

phpcs -p /MODULE/ --standard=PHPCompatibility --runtime-set testVersion 8.0 --extensions=php,module,inc,install,test,profile,theme

The command works fine. However, I am supposed to receive following error

"FILE: /contrib/content_sync/src/Form/ContentImportTrait.php
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FOUND 0 ERRORS AND 2 WARNINGS AFFECTING 2 LINES
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  55 | WARNING | Declaring a required parameter after an optional one is deprecated since PHP 8.0. Parameter $serializer_context is optional, while parameter $context is required.
 116 | WARNING | Declaring a required parameter after an optional one is deprecated since PHP 8.0. Parameter $serializer_context is optional, while parameter $context is required.
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FILE: /content_sync/src/Form/ContentExportTrait.php
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FOUND 0 ERRORS AND 1 WARNING AFFECTING 1 LINE
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 85 | WARNING | Declaring a required parameter after an optional one is deprecated since PHP 8.0. Parameter $serializer_context is optional, while parameter $context is required.
----------------------------------------------------------------------------------------------------------------"

Steps to reproduce

Proposed resolution

Remaining tasks

User interface changes

API changes

Data model changes