Add participant is_test field to views

[magnolia61]

BEFORE
The participant is_test field was missing from drupal views

AFTER
The participant is_test field is added to drupal views

[civibot]

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[seamuslee001]

(CiviCRM Review Template WORD-1.2)

• General standards
  • (r-explain) Pass
  • (r-user) Pass
  • (r-doc) Pass
  • (r-run) Pass replicated the issue and confirmed this does correct filtering on the view and that the select also works in the view
• Developer standards
  • (r-tech) Pass
  • (r-code) Pass
  • (r-maint) Pass
  • (r-test) Pass