How to suppress the Magento coding standard validation tool warnings?

github.com/squizlabs/PHP_CodeSniffer/wiki/Advanced-Usage

Please note that the Magento Marketplace’s automatic technical validation tool ignores such suppressions (e.g. // @codingStandardsIgnoreLine):

So, a suppression will not help you to upload your extension to Magento Marketplace.
If you think, that the Magento code validation tool («marketplace-eqp») reacts with a false positive on your extension, then I recommend to report in in the official issue tracker.