### Summary

Running `ansible-doc -l` generates 430 deprecation warnings on stderr before printing anything to stdout.
```
[DEPRECATION WARNING]: amazon.aws.aws_az_facts has been deprecated.
aws_az_facts was renamed in Ansible 2.9 to aws_az_info. Please update your
tasks. This feature will be removed from amazon.aws in a release after
2022-06-01. Deprecation warnings can be disabled by setting
deprecation_warnings=False in ansible.cfg.

[DEPRECATION WARNING]: amazon.aws.aws_caller_facts has been deprecated.
aws_caller_facts was renamed in Ansible 2.9 to aws_caller_info. Please update
your tasks. This feature will be removed from amazon.aws in a release after
2021-12-01. Deprecation warnings can be disabled by setting
deprecation_warnings=False in ansible.cfg.
...
```

### Issue Type

Bug Report

### Component Name

ansible-doc

### Ansible Version

```console
$ ansible-doc --version

ansible-doc 2.10.6
  config file = None
  configured module search path = [u'/home/charleshowes/.ansible/plugins/modules', u'/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/local/lib/python2.7/dist-packages/ansible
  executable location = /usr/local/bin/ansible-doc
  python version = 2.7.17 (default, Sep 30 2020, 13:38:04) [GCC 7.5.0]
```


### Configuration

```console
$ ansible-config dump --only-changed
(no output)
```


### OS / Environment

Ubuntu 18.04

### Steps to Reproduce

<!--- Paste example playbooks or commands between quotes below -->
```shell (paste below)
ansible-doc -l
```


### Expected Results

I expected to see a list of available plugins, and was shocked to have pages and pages of warnings.

### Actual Results

```console
$ ansible-doc -l 2>&1 | head

[DEPRECATION WARNING]: amazon.aws.aws_az_facts has been deprecated. 
aws_az_facts was renamed in Ansible 2.9 to aws_az_info. Please update your 
tasks. This feature will be removed from amazon.aws in a release after 
2022-06-01. Deprecation warnings can be disabled by setting 
deprecation_warnings=False in ansible.cfg.
[DEPRECATION WARNING]: amazon.aws.aws_caller_facts has been deprecated. 
aws_caller_facts was renamed in Ansible 2.9 to aws_caller_info. Please update 
your tasks. This feature will be removed from amazon.aws in a release after 
2021-12-01. Deprecation warnings can be disabled by setting 
deprecation_warnings=False in ansible.cfg.

$ ansible-doc -l 2>&1 | grep -c 'DEPRECATION WARNING'

430
```


### Code of Conduct

- [X] I agree to follow the Ansible Code of Conduct
pkg = import_module(acr.n_python_package_name)
            except ImportError:
                return plugin_load_context.nope('Python package {0} not found'.format(acr.n_python_package_name))
        pkg_path = os.path.dirname(pkg.__file__)
        n_resource_path = os.path.join(pkg_path, n_resource)
        
        if os.path.exists(n_resource_path):
            return plugin_load_context.resolve(
                full_name, to_text(n_resource_path), acr.collection, 'found exact match for {0} in {1}'.format(full_name, acr.collection))
        if extension:
            
            return plugin_load_context.nope('no match for {0} in {1}'.format(to_text(n_resource), acr.collection))
        
        found_files = [f
                       for f in glob.iglob(os.path.join(pkg_path, n_resource) + '.*')
                       if os.path.isfile(f) and not f.endswith(C.MODULE_IGNORE_EXTS)]
        if not found_files:
            return plugin_load_context.nope('failed fuzzy extension match for {0} in {1}'.format(full_name, acr.collection))
        if len(found_files) > 1:
            
            pass
        return plugin_load_context.resolve(
            full_name, to_text(found_files[0]), acr.collection, 'found fuzzy extension match for {0} in {1}'.format(full_name, acr.collection))
    def find_plugin(self, name, mod_type='', ignore_deprecated=False, check_aliases=False, collection_list=None):
        ''' Find a plugin named name '''
        result = self.find_plugin_with_context(name, mod_type, ignore_deprecated, check_aliases, collection_list)
        if result.resolved and result.plugin_resolved_path:
            return result.plugin_resolved_path
        return None
    def find_plugin_with_context(self, name, mod_type='', ignore_deprecated=False, check_aliases=False, collection_list=None):