### 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
template_data['name'] = template_data.pop('collection_name')
                    meta_value = GalaxyCLI._get_skeleton_galaxy_yml(os.path.join(root, rel_root, f), template_data)
                    b_dest_file = to_bytes(os.path.join(obj_path, rel_root, filename), errors='surrogate_or_strict')
                    with open(b_dest_file, 'wb') as galaxy_obj:
                        galaxy_obj.write(to_bytes(meta_value, errors='surrogate_or_strict'))
                elif ext == ".j2" and not in_templates_dir:
                    src_template = os.path.join(root, f)
                    dest_file = os.path.join(obj_path, rel_root, filename)
                    template_data = to_text(loader._get_file_contents(src_template)[0], errors='surrogate_or_strict')
                    b_rendered = to_bytes(templar.template(template_data), errors='surrogate_or_strict')
                    with open(dest_file, 'wb') as df:
                        df.write(b_rendered)
                else:
                    f_rel_path = os.path.relpath(os.path.join(root, f), obj_skeleton)
                    shutil.copyfile(os.path.join(root, f), os.path.join(obj_path, f_rel_path))
            for d in dirs:
                b_dir_path = to_bytes(os.path.join(obj_path, rel_root, d), errors='surrogate_or_strict')
                if not os.path.exists(b_dir_path):
                    os.makedirs(b_dir_path)
        display.display("- %s %s was created successfully" % (galaxy_type.title(), obj_name))
    def execute_info(self):
        """
        prints out detailed information about an installed role as well as info available from the galaxy API.
        """
        roles_path = context.CLIARGS['roles_path']
        data = ''
        for role in context.CLIARGS['args']:
            role_info = {'path': roles_path}
            gr = GalaxyRole(self.galaxy, self.lazy_role_api, role)
            install_info = gr.install_info