### Summary

To reproduce, run these commands where `ns.col` is the name of a collection you do not have installed and the value of `-p` is a valid collection path that exists:

`ansible-galaxy collection list ns.col -p collections/`
`$?`

The output of $? on devel is 0, but since the collection wasn't found it should be 1. The same issue exists for listing specific roles that do not exist.

To fix:
1. [This method](https://github.com/ansible/ansible/blob/stable-2.14/lib/ansible/cli/galaxy.py#L1494-L1502) needs to return the correct exit code from `execute_list_role` and `execute_list_collection`.

2. `execute_list_collection` and `execute_list_role` will need to be fixed to return 1 if a collection/role was requested and not found.
For example, on [this line ](https://github.com/ansible/ansible/blob/stable-2.14/lib/ansible/cli/galaxy.py#L1680) add
```python
        if not collection_found and collection_name:
            return 1
```

3. Add a new test to [this file](https://github.com/ansible/ansible/blob/stable-2.14/test/integration/targets/ansible-galaxy-collection/tasks/list.yml), similar to [this one](https://github.com/ansible/ansible/blob/stable-2.14/test/integration/targets/ansible-galaxy-collection/tasks/list.yml#L111-L116) that lists a single collection that does not exist. Then add an assert task following it to test that the command result's rc is 1.

4. Add a `bugfixes` [changelog fragment](https://docs.ansible.com/ansible/latest/community/development_process.html#creating-a-changelog-fragment).

### Issue Type

Bug Report

### Component Name

ansible-galaxy

### Ansible Version

```console
$ ansible --version
ansible [core 2.15.0.dev0]
```


### Configuration

```console
# if using a version older than ansible-core 2.12 you should omit the '-t all'
$ ansible-config dump --only-changed -t all
```


### OS / Environment

N/A

### Steps to Reproduce

<!--- Paste example playbooks or commands between quotes below -->
```bash (paste below)
ansible-galaxy collection list ns.col -p collections/
$?
```

### Expected Results

1

### Actual Results

```console
0
```


### Code of Conduct

- [X] I agree to follow the Ansible Code of Conduct
'''command to manage Ansible roles in shared repositories, the default of which is Ansible Galaxy *https://galaxy.ansible.com*.'''
    name = 'ansible-galaxy'
    SKIP_INFO_KEYS = ("name", "description", "readme_html", "related", "summary_fields", "average_aw_composite", "average_aw_score", "url")
    def __init__(self, args):
        self._raw_args = args
        self._implicit_role = False
        if len(args) > 1:
            
            if args[1] not in ['-h', '--help', '--version'] and 'role' not in args and 'collection' not in args:
                
                args.insert(1, 'role')
                self._implicit_role = True
            
            if args[1:3] == ['role', 'login']:
                display.error(
                    "The login command was removed in late 2020. An API key is now required to publish roles or collections "
                    "to Galaxy. The key can be found at https://galaxy.ansible.com/me/preferences, and passed to the "
                    "ansible-galaxy CLI via a file at {0} or (insecurely) via the `--token` "
                    "command-line argument.".format(to_text(C.GALAXY_TOKEN_PATH)))
                sys.exit(1)
        self.api_servers = []
        self.galaxy = None
        self.lazy_role_api = None
        super(GalaxyCLI, self).__init__(args)
    def init_parser(self):