Add slack endpoint back in

[maxneuvians]

The old app included the following code:

def slack():
    data = parse_qs(app.current_request.raw_body.decode())
    if "text" in data:
        return {
            "response_type": "ephemeral",
            "blocks": [
                {
                    "type": "section",
                    "text": {
                        "type": "mrkdwn",
                        "text": "Share your secret with the following link: \n>https://%s/en/view/%s \n Note: your link is valid for the next 60 minutes"
                        % (
                            app.current_request.headers["host"],
                            encrypt_and_save(
                                data["text"][0],
                                int(time.time()) + 60 * 1000,
                            ),
                        ),
                    },
                }
            ],
        }
    else:
        return {
            "response_type": "ephemeral",
            "text": "Sorry, an error occured generating your secret.",
        }

This should be refactored and rethought to meet the needs of a slack command.

[maxneuvians]

This might actually be a better fit for the SRE bot