[CLI] Clarifying the config file when using the CLI tool

[ppf2]

A couple of feedback on the CLI tool/documentation (part of this feedback is more of a documentation suggestion, but there's not a docs label when creating the new issue here):

• The ./bin/connectors login does not support passing in SSL parameters to specify the CA cert. It's unclear what users need to do in order to connect with a HTTPS enabled Elasticsearch cluster. If the answer is for users to use -c to pass in their own config.yml file with the Elasticsearch connection settings (along with the SSL ones), it will be helpful to clarify in the docs.
• Running ./connectors connector --help returns:

$ ./connectors connector --help
Traceback (most recent call last):
  File "/Users/<user>/Downloads/connectors-main/bin/./connectors", line 33, in <module>
    sys.exit(load_entry_point('elasticsearch-connectors', 'console_scripts', 'connectors')())
  File "/Users/<user>/Downloads/connectors-main/connectors/connectors_cli.py", line 590, in main
    cli()
  File "/Users/<user>/Downloads/connectors-main/lib/python3.10/site-packages/click/core.py", line 1157, in __call__
    return self.main(*args, **kwargs)
  File "/Users/<user>/Downloads/connectors-main/lib/python3.10/site-packages/click/core.py", line 1078, in main
    rv = self.invoke(ctx)
  File "/Users/<user>/Downloads/connectors-main/lib/python3.10/site-packages/click/core.py", line 1685, in invoke
    super().invoke(ctx)
  File "/Users/<user>/Downloads/connectors-main/lib/python3.10/site-packages/click/core.py", line 1434, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/Users/<user>/Downloads/connectors-main/lib/python3.10/site-packages/click/core.py", line 783, in invoke
    return __callback(*args, **kwargs)
  File "/Users/<user>/Downloads/connectors-main/lib/python3.10/site-packages/click/decorators.py", line 33, in new_func
    return f(get_current_context(), *args, **kwargs)
  File "/Users/<user>/Downloads/connectors-main/connectors/connectors_cli.py", line 58, in cli
    ctx.obj["config"] = load_config(ctx, config)
  File "/Users/<user>/Downloads/connectors-main/connectors/connectors_cli.py", line 43, in load_config
    raise FileNotFoundError(msg)
FileNotFoundError: .cli/config.yml is not found

It's unclear what users need to do here, will they have to manually create the .cli/config.yml file first? A better error message may be to tell the user to use -c parameter and their own config.yml.

• When we talk about -c <config-file-path.yml>, it can be helpful to add some context on which config.yml we are referring to, since there's a mention of .cli/config.yml as well. Is this the ../config.yml at the root level of the downloaded repository? If so, any considerations on what needs to be specified in the config.yml to use with the CLI tool? (e.g. minimum set of settings like ES connection settings in order for the CLI to work, etc..)