Drupal Coding Standards Issues | phpcs

Problem/Motivation

Getting following error/warnings

FILE: /var/www/html/modules/contrib/error_page/tests/modules/error_page_test/error_page_test.routing.yml
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FOUND 0 ERRORS AND 4 WARNINGS AFFECTING 4 LINES
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6 | WARNING | Open page callback found, please add a comment before the line why there is no access restriction
12 | WARNING | Open page callback found, please add a comment before the line why there is no access restriction
18 | WARNING | Open page callback found, please add a comment before the line why there is no access restriction
26 | WARNING | Open page callback found, please add a comment before the line why there is no access restriction
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FILE: /var/www/html/modules/contrib/error_page/tests/src/Functional/ErrorPageTest.php
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FOUND 3 ERRORS AFFECTING 3 LINES
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102 | ERROR | unserialize() is insecure unless allowed classes are limited. Use a safe format like JSON or use the allowed_classes option.
117 | ERROR | unserialize() is insecure unless allowed classes are limited. Use a safe format like JSON or use the allowed_classes option.
134 | ERROR | unserialize() is insecure unless allowed classes are limited. Use a safe format like JSON or use the allowed_classes option.
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FILE: /var/www/html/modules/contrib/error_page/src/EventSubscriber/ErrorPageExceptionLoggingSubscriber.php
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FOUND 1 ERROR AFFECTING 1 LINE
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25 | ERROR | [x] Use null coalesce operator instead of ternary operator.
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PHPCBF CAN FIX THE 1 MARKED SNIFF VIOLATIONS AUTOMATICALLY
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Time: 1.95 secs; Memory: 6MB

Steps to reproduce

Run following command

phpcs --standard=Drupal,DrupalPractice --extensions=php,module,inc,install,test,profile,theme,css,info,txt,md,yml modules/contrib/terms_of_use/

Proposed resolution

Above error/warnings need to be fixed.