Description for the @return value is missing

Thanks for starting this @Rohit Rana, however - I have implemented a personal policy of only providing credit for code standards updates to new contributers who have not already recieved a credit for code standards updates, so I will be removing credit from this issue.

Also, please do not open coding standards updates with a specific title for an individial problem. Open a single issue for ALL required code standards fixes unless the module is so gigantic that it becomes impossible to manage. I have changed this issue to that effect.

Finally, I would also like to point out that rather than blindly following the suggestion provided by phpcs regarding the @return value documentation, if there is nothing specific to write in said documentation, the return typehint should suffice and the doc-comment can be deleted which will also satisfy phpcs.

Now that GitLab CI is in place and it's standard practice for contrib modules to include PHPCS tests I'm retracting my credit policy. All normal credits will be applied for this issue.