Require company logo

I did it by going into wp-job-manager\includes\forms
Opening file: class-wp-job-manager-form-submit-job.php
Around line 206 you’ll see:

‘company_logo’ => array(
‘label’ => __( ‘Product image’, ‘wp-job-manager’ ),
‘type’ => ‘file’,
‘required’ => false,

I changed the link Required to equal true.

However, if you are not accustom to editing code you may want to hire someone. Also if the plugin is updated that change will probably vanish with the updated plugin version.