Fix Coding Standard

FILE:/datetime_flatpickr/src/Plugin/Field/FieldWidget/DateTimeFlatPickrWidget.php
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FOUND 9 ERRORS AND 3 WARNINGS AFFECTING 10 LINES
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   5 | WARNING | [x] Unused use statement
 158 | ERROR   | [x] Expected 1 space after "="; 2 found
 159 | ERROR   | [x] Functions must not contain multiple empty lines in a row; found 2 empty lines
 215 | ERROR   | [x] Inline comments must end in full-stops, exclamation marks, question marks, colons, or closing parentheses
 227 | WARNING | [ ] Line exceeds 80 characters; contains 89 characters
 227 | ERROR   | [x] Inline comments must end in full-stops, exclamation marks, question marks, colons, or closing parentheses
 229 | WARNING | [ ] Line exceeds 80 characters; contains 83 characters
 470 | ERROR   | [ ] Parameter $items is not described in comment
 476 | ERROR   | [ ] Parameter tags must be grouped together in a doc comment
 476 | ERROR   | [ ] Doc comment for parameter $item does not match actual variable name $items
 477 | ERROR   | [x] Parameter comment indentation must be 3 spaces, found 2 spaces
 581 | ERROR   | [ ] If the line declaring an array spans longer than 80 characters, each element should be broken into its own line
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PHPCBF CAN FIX THE 6 MARKED SNIFF VIOLATIONS AUTOMATICALLY
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Time: 175ms; Memory: 10MB