<!--- Verify first that your issue is not already reported on GitHub -->
<!--- Also test if the latest release and devel branch are affected too -->
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##### SUMMARY
<!--- Explain the problem briefly below -->
We publish semver collection (vyos.vyos:0.0.1-dev58) to ansible galaxy, however by default it seems ansible-galaxy client will not be able to find it. You must specific the version number directly to fetch it.

https://galaxy.ansible.com/vyos/vyos


EDIT:

This is working as expect, but it would be nice to Include:

   --pre                       Include pre-release and development versions. By default, ansible-galaxy only finds stable versions.

##### ISSUE TYPE
- Bug Report

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

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
ansible 2.9.1
```

##### CONFIGURATION
<!--- Paste verbatim output from "ansible-config dump --only-changed" between quotes -->
```paste below

```


##### STEPS TO REPRODUCE
<!--- Describe exactly how to reproduce the problem, using a minimal test-case -->

<!--- Paste example playbooks or commands between quotes below -->
```yaml
$ ansible-galaxy collection install vyos.vyos -p /tmp/11123
[WARNING]: The specified collections path '/tmp/11123' is not part of the configured Ansible collections paths '/home/pabelanger/.ansible/collections:/usr/share/ansible/collections'. The
installed collection won't be picked up in an Ansible run.

Process install dependency map
ERROR! Cannot meet requirement * for dependency vyos.vyos from source 'https://galaxy.ansible.com/api/'. Available versions before last requirement added: 
Requirements from:
	base - 'vyos.vyos:*'
(venv) [pabelanger@localhost openstack]$ ansible-galaxy collection install vyos.vyos:0.0.1-dev57 -p /tmp/11123
[WARNING]: The specified collections path '/tmp/11123' is not part of the configured Ansible collections paths '/home/pabelanger/.ansible/collections:/usr/share/ansible/collections'. The
installed collection won't be picked up in an Ansible run.

Process install dependency map
Starting collection install process
Installing 'vyos.vyos:0.0.1-dev57' to '/tmp/11123/ansible_collections/vyos/vyos'
```

<!--- HINT: You can paste gist.github.com links for larger files -->

##### EXPECTED RESULTS
<!--- Describe what you expected to happen when running the steps above -->
vyos.vyos collection to be found and installed

##### ACTUAL RESULTS
<!--- Describe what actually happened. If possible run with extra verbosity (-vvvv) -->

<!--- Paste verbatim command output between quotes -->
```paste below

```

test_dir = to_bytes(tmp_path_factory.mktemp('test-ÅÑŚÌβŁÈ Collections Input'))
    test_file = os.path.join(test_dir, b'fake.tar.gz')
    with open(test_file, 'wb') as test_obj:
        test_obj.write(b"\x00\x01\x02\x03")
    expected = "Collection artifact at '%s' is not a valid tar file." % to_native(test_file)
    with pytest.raises(AnsibleError, match=expected):
        collection.CollectionRequirement.from_tar(test_file, True, True)
def test_build_requirement_from_tar_no_manifest(tmp_path_factory):
    test_dir = to_bytes(tmp_path_factory.mktemp('test-ÅÑŚÌβŁÈ Collections Input'))
    json_data = to_bytes(json.dumps(
        {
            'files': [],
            'format': 1,
        }
    ))
    tar_path = os.path.join(test_dir, b'ansible-collections.tar.gz')
    with tarfile.open(tar_path, 'w:gz') as tfile:
        b_io = BytesIO(json_data)
        tar_info = tarfile.TarInfo('FILES.json')
        tar_info.size = len(json_data)
        tar_info.mode = 0o0644
        tfile.addfile(tarinfo=tar_info, fileobj=b_io)
    expected = "Collection at '%s' does not contain the required file MANIFEST.json." % to_native(tar_path)
    with pytest.raises(AnsibleError, match=expected):
        collection.CollectionRequirement.from_tar(tar_path, True, True)
def test_build_requirement_from_tar_no_files(tmp_path_factory):