Fix phpcs Error and Warnings

PHPCS reported the following errors and warnings:

FILE: /banana_dashboard/css/banana_dashboard.css
----------------------------------------------------------------------------------------------------------
FOUND 29 ERRORS AFFECTING 29 LINES
----------------------------------------------------------------------------------------------------------
  2 | ERROR | [x] Line indented incorrectly; expected 2 spaces, found 4
  3 | ERROR | [x] Line indented incorrectly; expected 2 spaces, found 4
  4 | ERROR | [x] Line indented incorrectly; expected 2 spaces, found 4
  5 | ERROR | [x] Line indented incorrectly; expected 2 spaces, found 4
  6 | ERROR | [x] Line indented incorrectly; expected 2 spaces, found 4
  7 | ERROR | [x] Line indented incorrectly; expected 2 spaces, found 4
  8 | ERROR | [x] Line indented incorrectly; expected 2 spaces, found 4
  9 | ERROR | [x] Line indented incorrectly; expected 2 spaces, found 4
 10 | ERROR | [x] Line indented incorrectly; expected 2 spaces, found 4
 11 | ERROR | [x] Line indented incorrectly; expected 2 spaces, found 4
 12 | ERROR | [x] Line indented incorrectly; expected 2 spaces, found 4
 13 | ERROR | [x] Line indented incorrectly; expected 2 spaces, found 4
 14 | ERROR | [x] Line indented incorrectly; expected 2 spaces, found 4
 15 | ERROR | [x] Line indented incorrectly; expected 2 spaces, found 4
 16 | ERROR | [x] Line indented incorrectly; expected 2 spaces, found 4
 17 | ERROR | [x] Line indented incorrectly; expected 2 spaces, found 4
 18 | ERROR | [x] Line indented incorrectly; expected 2 spaces, found 4
 22 | ERROR | [x] Line indented incorrectly; expected 2 spaces, found 4
 23 | ERROR | [x] Line indented incorrectly; expected 2 spaces, found 4
 24 | ERROR | [x] Line indented incorrectly; expected 2 spaces, found 4
 27 | ERROR | [x] Expected 1 space before opening brace of class definition; 0 found
 28 | ERROR | [x] Line indented incorrectly; expected 2 spaces, found 4
 32 | ERROR | [x] Line indented incorrectly; expected 2 spaces, found 4
 36 | ERROR | [x] Line indented incorrectly; expected 2 spaces, found 4
 37 | ERROR | [x] Line indented incorrectly; expected 2 spaces, found 4
 38 | ERROR | [x] Line indented incorrectly; expected 2 spaces, found 4
 42 | ERROR | [x] Line indented incorrectly; expected 2 spaces, found 4
 43 | ERROR | [x] Expected 1 newline at end of file; 2 found
 44 | ERROR | [x] Additional whitespace found at end of file
----------------------------------------------------------------------------------------------------------
PHPCBF CAN FIX THE 29 MARKED SNIFF VIOLATIONS AUTOMATICALLY
----------------------------------------------------------------------------------------------------------


FILE: /banana_dashboard/src/Controller/BananaDashboardController.php
------------------------------------------------------------------------------------------------------------------------------
FOUND 1 ERROR AND 1 WARNING AFFECTING 2 LINES
------------------------------------------------------------------------------------------------------------------------------
 22 | WARNING | [ ] \Drupal calls should be avoided in classes, use dependency injection instead
 39 | ERROR   | [x] Use null coalesce operator instead of ternary operator.
------------------------------------------------------------------------------------------------------------------------------
PHPCBF CAN FIX THE 1 MARKED SNIFF VIOLATIONS AUTOMATICALLY