Find / add tests for API keys!

We have a bunch of regex which do not have tests:

- [ ] Facebook (no idea how to use their API)
- [ ] Twitter (I am bannned from making a bot)
- [x] GitHub App Token does not exist according to google
- [ ] LinkedIn Client ID - changed to hash
- [ ] LinkedIn Secret Key - changed to hash
- [x] GitHub Access Token - same as personal access token?
- [ ] Stripe Restricted API Token - cant find
- [x] Square Access Token - no examples
- [ ] Square OAuth Token - no examples
- [ ] PayPal/Braintree Access Token - no examples
- [ ] MWS Auth Token - no examples
- [ ] Picatic API Key - no examples
- [ ] Google OAuth Access Key - no example
- [ ] Google OAuth ID - no examples
- [x] StackHawk API Key
- [ ] NuGet API Key
- [ ] SendGrid Token
- [ ] Zoho Webhook Token
- [ ] New Relic Admin API Key
- [ ] New Relic Insights API Key
- [x] New Relic REST API Key
- [x] New Relic Synthetics Location Key
- [ ] Microsoft Teams Webhook
- [ ] Google FCM Server Key

- [x] Discord Webhook

- [ ] Cloudinary Credentials

- [x] Bitly secret key

- [x] PyPi Upload Token

- [ ] Shopify Private App Access Token

- [ ] Shopify Custom App Access Token

- [ ] Shopify Access Token

- [ ] Shopify Shared Secret

- [ ] Dynatrace Token

- [ ] Google Cloud Platform API Key

- [x] Mailchimp API Key

Find some API keys and make some tests! Look here to find our tests, just copy one of them! https://github.com/bee-san/pyWhat/blob/main/tests/test_regex_identifier.py

Start with tests/test_regex_identifier.py, which the issue identifies as the template for adding API-key tests. Choose an unchecked API-key pattern with usable examples, add representative test coverage, and run the relevant test file to confirm the regexes identify the intended keys without false matches.

Written by the indexing model from the issue text.