--config-dir is not actually used

[rorydonaldson]

Describe the bug

When specifying --config-dir or -c - the value is not actually used.

To Reproduce
Steps to reproduce the behavior:

Run the following in a fresh environment without ~/.edr/ present.

edr send-report --slack-token xxxx --slack-channel-name xxxx -c /mounted/.edr

You'll observe that the .edr directory is created at ~/.edr

Expected behavior

Config is initialised as follows:
config = Config()

In config/config.py, self.config_dir is set to the value of DEFAULT_CONFIG_DIR.

DEFAULT_CONFIG_DIR is never overwritten with anything other than the value of str(Path.home() / ".edr")

Environment (please complete the following information):

• Elementary CLI (edr) version: 0.20.0

Would you be willing to contribute a fix for this issue?
Yes