Evikulov/readme update

[EVikulov]

Description

Please include a summary of the change and which issue is fixed. Please also include relevant motivation and context. List any dependencies that are required for this change.

Fixes # (issue)

Type of change

Please delete options that are not relevant.

• [ ] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [ ] This change requires a documentation update

Checklist:

• [ ] My code follows the style guidelines of this project
• [ ] I have performed a self-review of my own code
• [ ] I have commented my code, particularly in hard-to-understand areas
• [ ] I have made corresponding changes to the documentation
• [ ] My changes generate no new warnings
• [ ] Any dependent changes have been merged and published in downstream modules

[DenTray]

@EVikulov could you please rewrite the "Installation" block:

1. Remove Composer/Laravel/Plugin headings
2. Text about the Laravel 5.5. version should be decorated as Note
3. The second point in the current Laravel heading should be simplified to Run php artisan vendor:publish
4. Hightlight all class-related words (naespaces, classes, etc.) as a code (e.g. Http/Kernel.php)
5. In the second point in the current Plugin heading please rewrite "Use" word to "Add"
6. The third point in the current Plugin heading should be removed
7. Rewrite the current sentence to "Add the following env variables"
8. Remove fourth point about the env variables
9. Hightlight "Please note that this way will be removed after updating PHPUnit up to 10 version (https://github.com/sebastianbergmann/phpunit/issues/4676)" as a note
10. Rewrite the description annotation in the request class example
11. Rewrite the field annotation from the @some_field to the real field from the class (@is_active)