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##### SUMMARY
The "source" folder of my collection contains several files that are not directly related to the collection itself. E.g. a `.gitignore`, a `.github` folder, a `Makefile` etc.
When using `ansible-galaxy collection build <folder>`, these files are included in the generated tarball. This is especially hurtful when the source folder also contains a Python venv that I use for developing.

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
ansible-galaxy

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
ansible 2.9.0.dev0
  config file = /etc/ansible/ansible.cfg
  configured module search path = [u'/home/egolov/.ansible/plugins/modules', u'/usr/share/ansible/plugins/modules']
  ansible python module location = /home/egolov/Devel/ansible/ansible/lib/ansible
  executable location = /home/egolov/Devel/ansible/ansible/bin/ansible
  python version = 2.7.15 (default, Oct 15 2018, 15:26:09) [GCC 8.2.1 20180801 (Red Hat 8.2.1-2)]

```

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

##### OS / ENVIRONMENT
Fedora


##### STEPS TO REPRODUCE
Build a collection :)

##### EXPECTED RESULTS
I'd expect only collection-relevant files/folders (those that are listed in the spec/docs) to be included.


##### ADDITIONAL INFORMATION
Alternatively, a ignore file as suggested by @bcoca  in https://github.com/ansible/ansible/pull/59121/files#r304554334 could be a fix for this.

from ansible.cli.arguments import option_helpers as opt_help
from ansible.errors import AnsibleError, AnsibleOptionsError
from ansible.galaxy import Galaxy, get_collections_galaxy_meta_info
from ansible.galaxy.api import GalaxyAPI
from ansible.galaxy.collection import build_collection, install_collections, publish_collection, \
    validate_collection_name
from ansible.galaxy.login import GalaxyLogin
from ansible.galaxy.role import GalaxyRole
from ansible.galaxy.token import BasicAuthToken, GalaxyToken, KeycloakToken, NoTokenSentinel
from ansible.module_utils.ansible_release import __version__ as ansible_version
from ansible.module_utils._text import to_bytes, to_native, to_text
from ansible.parsing.yaml.loader import AnsibleLoader
from ansible.playbook.role.requirement import RoleRequirement
from ansible.utils.display import Display
from ansible.utils.plugin_docs import get_versioned_doclink
display = Display()
class GalaxyCLI(CLI):
    '''command to manage Ansible roles in shared repositories, the default of which is Ansible Galaxy *https://galaxy.ansible.com*.'''
    SKIP_INFO_KEYS = ("name", "description", "readme_html", "related", "summary_fields", "average_aw_composite", "average_aw_score", "url")
    def __init__(self, args):
        
        if len(args) > 1 and args[1] not in ['-h', '--help', '--version'] and 'role' not in args and 'collection' not in args:
            
            
            idx = 2 if args[1].startswith('-v') else 1
            args.insert(idx, 'role')
        self.api_servers = []
        self.galaxy = None
        super(GalaxyCLI, self).__init__(args)
    def init_parser(self):