### Summary

If a galaxy requirements file contains collections that have signatures defined, then `ansible-galaxy role install` with that requirements file fails because a keyring is not supplied.

### Issue Type

Bug Report

### Component Name

ansible-galaxy

### Ansible Version

```console
$ ansible --version

ansible [core 2.13.0.dev0] (devel ff184b0815) last updated 2022/03/24 16:21:31 (GMT -400)
  config file = /home/shrews/.ansible.cfg
  configured module search path = ['/home/shrews/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /home/shrews/Devel/github/Shrews/ansible/lib/ansible
  ansible collection location = /home/shrews/.ansible/collections:/usr/share/ansible/collections
  executable location = /home/shrews/Devel/github/Shrews/ansible/bin/ansible
  python version = 3.9.7 (default, Sep 10 2021, 14:59:43) [GCC 11.2.0]
  jinja version = 3.1.0
  libyaml = True
```


### Configuration

```console
$ ansible-config dump --only-changed

DEFAULT_HOST_LIST(/home/shrews/.ansible.cfg) = ['/home/shrews/Devel/ansible/hosts.yaml']
```


### OS / Environment

Ubuntu 21.10

### Steps to Reproduce

<!--- Paste example playbooks or commands between quotes below -->
```yaml (paste below)

$ cat req.yml 
collections:
  - name: community.mysql
    signatures:
      - file:///home/shrews/test.asc

$ ansible-galaxy role install -r req.yml 
ERROR! Signatures were provided to verify community.mysql but no keyring was configured.
```


### Expected Results

`role install` should ignore collection signatures

### Actual Results

```console
$ ansible-galaxy role install -r req.yml -vvvv

ansible-galaxy [core 2.13.0.dev0] (devel ff184b0815) last updated 2022/03/24 16:21:31 (GMT -400)
  config file = /home/shrews/.ansible.cfg
  configured module search path = ['/home/shrews/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /home/shrews/Devel/github/Shrews/ansible/lib/ansible
  ansible collection location = /home/shrews/.ansible/collections:/usr/share/ansible/collections
  executable location = /home/shrews/Devel/github/Shrews/ansible/bin/ansible-galaxy
  python version = 3.9.7 (default, Sep 10 2021, 14:59:43) [GCC 11.2.0]
  jinja version = 3.1.0
  libyaml = True
Using /home/shrews/.ansible.cfg as config file
Reading requirement file at '/home/shrews/req.yml'
ERROR! Signatures were provided to verify community.mysql but no keyring was configured.
```


### Code of Conduct

- [X] I agree to follow the Ansible Code of Conduct
req_type = 'galaxy'
            elif (
                    req_name is not None
                    and _is_concrete_artifact_pointer(req_name)
            ):
                src_path, req_name = req_name, None
            else:
                dir_tip_tmpl = (  
                    '\n\nTip: Make sure you are pointing to the right '
                    'subdirectory — `{src!s}` looks like a directory '
                    'but it is neither a collection, nor a namespace '
                    'dir.'
                )
                if req_source is not None and os.path.isdir(req_source):
                    tip = dir_tip_tmpl.format(src=req_source)
                elif req_name is not None and os.path.isdir(req_name):
                    tip = dir_tip_tmpl.format(src=req_name)
                elif req_name:
                    tip = '\n\nCould not find {0}.'.format(req_name)
                else:
                    tip = ''
                raise AnsibleError(  # 
                    'Neither the collection requirement entry key '
                    "'name', nor 'source' point to a concrete "
                    "resolvable collection artifact. Also 'name' is "
                    'not an FQCN. A valid collection name must be in '
                    'the format <namespace>.<collection>. Please make '
                    'sure that the namespace and the collection name '
                    ' contain characters from [a-zA-Z0-9_] only.'
                    '{extra_tip!s}'.format(extra_tip=tip),