(Filling out the following details about bugs will help us solve your issue sooner.)

Steps to reproduce:

(Share the commands to run, source code, and project settings (e.g., setup.py))

1. Try setting up an app to point to a different slack url that does not include a trailing /
2. app = App(token=os.environ.get("SLACK_BOT_TOKEN"), client=WebClient(os.environ.get("SLACK_BOT_TOKEN"), "https://example.slack.com/api"))
3. This will fail 🔴
4. Add a trailing /
app = App(token=os.environ.get("SLACK_BOT_TOKEN"), client=WebClient(os.environ.get("SLACK_BOT_TOKEN"), "https://example.slack.com/api/"))
5. This will pass 🟢

Expected result:

app = App(token=os.environ.get("SLACK_BOT_TOKEN"), client=WebClient(os.environ.get("SLACK_BOT_TOKEN"), "https://example.slack.com/api"))

Should provide an informative error or format the slack URL to work

Requirements

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