### Summary

The help from ``ansible-galaxy collection verify`` reads:
```
positional arguments:
  collection_name       The collection(s) name or path/url to a tar.gz collection artifact. This is mutually exclusive with --requirements-file.
```

However, only ``namespace.collection`` appears supported.

### Issue Type

Bug Report

### Component Name

ansible-galaxy

### Ansible Version

```console
ansible [core 2.11.6] 
  config file = /etc/ansible/ansible.cfg
  configured module search path = ['/home/dmsimard/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /home/dmsimard/dev/virtualenvs/ansible/lib64/python3.9/site-packages/ansible
  ansible collection location = /home/dmsimard/.ansible/collections:/usr/share/ansible/collections
  executable location = /home/dmsimard/dev/virtualenvs/ansible/bin/ansible
  python version = 3.9.7 (default, Aug 30 2021, 00:00:00) [GCC 11.2.1 20210728 (Red Hat 11.2.1-1)]
  jinja version = 3.0.2
  libyaml = True
```


### Configuration

```console
not relevant
```


### OS / Environment

not relevant

### Steps to Reproduce

From ``ansible-galaxy collection verify --help``:
```
> ansible-galaxy collection verify --help
usage: ansible-galaxy collection verify [-h] [-s API_SERVER] [--token API_KEY] [-c] [-v] [-p COLLECTIONS_PATH] [-i] [--offline] [-r REQUIREMENTS] [collection_name ...]

positional arguments:
  collection_name       The collection(s) name or path/url to a tar.gz collection artifact. This is mutually exclusive with --requirements-file.
```
^ **The collection(s) name or path/url to a tar.gz collection artifact.**


However:
```
> wget https://galaxy.ansible.com/download/community-general-3.8.0.tar.gz
2021-10-19 12:37:28 (8.82 MB/s) - ‘community-general-3.8.0.tar.gz’ saved [2220728/2220728]

> ansible-galaxy collection verify community-general-3.8.0.tar.gz
ERROR! 'file' type is not supported. The format namespace.name is expected.

> ansible-galaxy collection verify https://galaxy.ansible.com/download/community-general-3.8.0.tar.gz
Downloading https://galaxy.ansible.com/download/community-general-3.8.0.tar.gz to /home/dmsimard/.ansible/tmp/ansible-local-821546820f8vxq/tmplac4iqqg/community-general-3.8.0-jg8r9knz
ERROR! 'url' type is not supported. The format namespace.name is expected.
```

### Expected Results

Either it should work or the help text should be updated.

### Actual Results

```console
> wget https://galaxy.ansible.com/download/community-general-3.8.0.tar.gz
2021-10-19 12:37:28 (8.82 MB/s) - ‘community-general-3.8.0.tar.gz’ saved [2220728/2220728]

> ansible-galaxy collection verify community-general-3.8.0.tar.gz
ERROR! 'file' type is not supported. The format namespace.name is expected.

> ansible-galaxy collection verify https://galaxy.ansible.com/download/community-general-3.8.0.tar.gz
Downloading https://galaxy.ansible.com/download/community-general-3.8.0.tar.gz to /home/dmsimard/.ansible/tmp/ansible-local-821546820f8vxq/tmplac4iqqg/community-general-3.8.0-jg8r9knz
ERROR! 'url' type is not supported. The format namespace.name is expected.
```


### Code of Conduct

- [X] I agree to follow the Ansible Code of Conduct
requirements = {
            'roles': [],
            'collections': [],
        }
        b_requirements_file = to_bytes(requirements_file, errors='surrogate_or_strict')
        if not os.path.exists(b_requirements_file):
            raise AnsibleError("The requirements file '%s' does not exist." % to_native(requirements_file))
        display.vvv("Reading requirement file at '%s'" % requirements_file)
        with open(b_requirements_file, 'rb') as req_obj:
            try:
                file_requirements = yaml_load(req_obj)
            except YAMLError as err:
                raise AnsibleError(
                    "Failed to parse the requirements yml at '%s' with the following error:\n%s"
                    % (to_native(requirements_file), to_native(err)))
        if file_requirements is None:
            raise AnsibleError("No requirements found in file '%s'" % to_native(requirements_file))
        def parse_role_req(requirement):
            if "include" not in requirement:
                role = RoleRequirement.role_yaml_parse(requirement)
                display.vvv("found role %s in yaml file" % to_text(role))
                if "name" not in role and "src" not in role:
                    raise AnsibleError("Must specify name or src for role")
                return [GalaxyRole(self.galaxy, self.api, **role)]
            else:
                b_include_path = to_bytes(requirement["include"], errors="surrogate_or_strict")
                if not os.path.isfile(b_include_path):
                    raise AnsibleError("Failed to find include requirements file '%s' in '%s'"
                                       % (to_native(b_include_path), to_native(requirements_file)))
                with open(b_include_path, 'rb') as f_include: