Rotate all API keys after Heroku security breach

[maxwofford]

Part of https://github.com/hackclub/hackclub/issues/1767

These tokens need to be rotated:

• [ ] AIRTABLE_KEY
• [ ] ATHUL_AUTH_TOKEN
• [ ] BUGSNAG_API_KEY
• [ ] CLOUD9_ACCESS_TOKEN
• [ ] CLOUD9_PASSWORD
• [ ] CLOUD9_TEAM_NAME
• [ ] DATABASE_URL
• [ ] GIPHY_API_KEY
• [ ] GITHUB_BOT_ACCESS_TOKEN
• [ ] GOOGLE_MAPS_API_KEY
• [ ] GUGGY_API_KEY
• [ ] HACKATHONS_SITE_REBUILD_HOOK
• [ ] HEROKU_POSTGRESQL_GOLD_URL
• [ ] MLH_LHD_API_KEY
• [ ] MODE_URL
• [ ] NUMERACY_URL
• [ ] REDIS_TLS_URL
• [ ] REDIS_URL
• [ ] S3_ACCESS_KEY_ID
• [ ] S3_SECRET_ACCESS_KEY
• [ ] SEGMENT_URL
• [ ] SEGMENT_WRITE_KEY
• [ ] SENTRY_DSN
• [ ] SIDEKIQ_HTTP_PASSWORD
• [ ] SKYLIGHT_AUTHENTICATION
• [ ] SLACK_ADMIN_ACCESS_TOKEN
• [ ] SLACK_ADMIN_PASSWORD
• [ ] SLACK_CLIENT_ID
• [ ] SLACK_CLIENT_SECRET
• [ ] SMTP_PASSWORD
• [ ] SMTP_USERNAME
• [ ] STREAK_API_KEY
• [ ] STRIPE_SECRET_KEY
• [ ] TWILIO_ACCOUNT_SID
• [ ] TWILIO_API_KEY
• [ ] ZAPIER_URL