include BOM in attachment when sending csv civireport via mail_report job

CRM/Report/Form.php

CRM/Report/Utils/Report.php

CRM/Utils/Mail.php

...t/Form/Contribute/fixtures/DetailPostalCodeTest-ascii.csv

...unit/CRM/Report/Form/Contribute/fixtures/report-ascii.csv

tests/phpunit/CRM/Report/Form/Contribute/fixtures/report.csv

tests/phpunit/CRM/Report/Form/TestCaseTest.php

tests/phpunit/CRM/Report/Utils/ReportTest.php

tests/phpunit/api/v3/JobTest.php