
currently an invalid collection will error out on docs sanity, but this is misleading since the problem is that the collection name itself is invalid, a previous test verifying this should be introduced to avoid confusion.

example currently:
```
Running sanity test 'ansible-doc' with Python 3.7
ERROR: Command "ansible-doc -t module cyberark.ansible-security-automation-collection.cyberark_account cyberark.ansible-security-automation-collection.cyberark_authentication cyberark.ansible-security-automation-collection.cyberark_credential cyberark.ansible-security-automation-collection.cyberark_user" returned exit status 250.
>>> Standard Error
[WARNING]: module cyberark.ansible-security-automation-collection.cyberark_account not found in: /dev/null:/home/abehl/work/src/anshul_ansible/ansible/lib/ansible/modules
ERROR! Unexpected Exception, this is probably a bug: cannot unpack non-iterable NoneType object
```
##### ISSUE TYPE
- Feature Idea

##### COMPONENT NAME
<!--- Write the short name of the module, plugin, task or feature below, use your best guess if unsure -->
ansible-test

'.xml',
        '.yaml',
        '.yml',
    }
    assume_binary = {
        '.bin',
        '.eot',
        '.gz',
        '.ico',
        '.iso',
        '.jpg',
        '.otf',
        '.p12',
        '.png',
        '.pyc',
        '.rpm',
        '.ttf',
        '.woff',
        '.woff2',
        '.zip',
    }
    ext = os.path.splitext(path)[1]
    if ext in assume_text:
        return False
    if ext in assume_binary:
        return True
    with open_binary_file(path) as path_fd:
        
        return b'\0' in path_fd.read(4096)
def generate_name(length=8):