Fix the issues reported by phpcs

Problem/Motivation

FILE: /var/www/html/vb/d_cont/virtual_select/README.md
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FOUND 0 ERRORS AND 5 WARNINGS AFFECTING 5 LINES
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17 | WARNING | Line exceeds 80 characters; contains 81 characters
19 | WARNING | Line exceeds 80 characters; contains 99 characters
28 | WARNING | Line exceeds 80 characters; contains 90 characters
39 | WARNING | Line exceeds 80 characters; contains 81 characters
48 | WARNING | Line exceeds 80 characters; contains 89 characters
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FILE: ...ml/vb/d_cont/virtual_select/src/Plugin/Field/FieldWidget/VirtualSelect.php
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FOUND 3 ERRORS AFFECTING 3 LINES
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33 | ERROR | [ ] Namespaced classes/interfaces/traits should be referenced
| | with use statements
44 | ERROR | [ ] Namespaced classes/interfaces/traits should be referenced
| | with use statements
75 | ERROR | [x] Expected 1 blank line after function; 2 found
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PHPCBF CAN FIX THE 1 MARKED SNIFF VIOLATIONS AUTOMATICALLY
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Time: 86ms; Memory: 10MB

Steps to reproduce

Execute the command: phpcs --standard=Drupal,DrupalPractice --extensions=php,module,inc,install,test,profile,theme,css,info,txt,md,yml,twig virtual_select/

Remaining tasks

Patch review