Error 500 when acceptance is required without signature

[diegogarciadev]

Please confirm you have done the following before posting your bug report:

• I have enabled debug mode
• I have read checked the Common Issues page

Describe the bug
When checkout with acceptance required but signature not required you will get an 500 error.
ErrorException: Undefined variable: sig_filename in /var/www/html/snipe-it/app/Http/Controllers/Account/AcceptanceController.php:109

To Reproduce
Steps to reproduce the behavior:

Expected behavior

Screenshots

    if ($request->input('asset_acceptance') == 'accepted') {

        $acceptance->accept($sig_filename);   <---------- $sig_filename will not exist if signature is disabled

        event(new CheckoutAccepted($acceptance));

        $return_msg = trans('admin/users/message.accepted');

    } else {

        $acceptance->decline($sig_filename);

Server (please complete the following information):

• Snipe-IT Version
• OS: [e.g. Ubuntu, CentOS]
• Web Server: [e.g. Apache, IIS]
• PHP Version

Desktop (please complete the following information):

• OS: [e.g. iOS]
• Browser [e.g. chrome, safari]
• Version [e.g. 22]

Smartphone (please complete the following information):

• Device: [e.g. iPhone6]
• OS: [e.g. iOS8.1]
• Browser [e.g. stock browser, safari]
• Version [e.g. 22]

Error Messages
[2020-10-27 13:33:40] production.ERROR: ErrorException: Undefined variable: sig_filename in /var/www/html/snipe-it/app/Http/Controllers/Account/AcceptanceController.php:109
Stack trace:
#0 /var/www/html/snipe-it/app/Http/Controllers/Account/AcceptanceController.php(109): Illuminate\Foundation\Bootstrap\HandleExceptions->handleError(8, 'Undefined varia...', '/var/www/html/s...', 109, Array)

Additional context

[diegogarciadev]

solved in #8589