Resolve PHPStan warnings found in GitLab CI runs

Only seeing the following errors, which are addressed in the MR:
$ phpcs --standard="Drupal,DrupalPractice" --extensions=php,module,inc,install,test,profile,theme,css,info,txt,md,yml .

FILE: /sfweb2lead_webform/src/Plugin/WebformHandler/SalesforceWebToLeadPostWebformHandler.php
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FOUND 1 ERROR AFFECTING 1 LINE
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 41 | ERROR | The array declaration extends to column 115 (the limit is 80). The array content should be split up over multiple lines
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FILE: /sfweb2lead_webform/src/EventSubscriber/BackwardsCompatibilitySubscriber.php
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FOUND 0 ERRORS AND 3 WARNINGS AFFECTING 3 LINES
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 29 | WARNING | \Drupal calls should be avoided in classes, use dependency injection instead
 35 | WARNING | \Drupal calls should be avoided in classes, use dependency injection instead
 42 | WARNING | \Drupal calls should be avoided in classes, use dependency injection instead
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Please review, Thanks!

Automatically closed - issue fixed for 2 weeks with no activity.