Update web-app.md

[singlebeam]

thubConfig.yaml

What

What is the reason for this change?

Cannot parse thubConfig.yaml due to missing quote

Why

Why is this change important?

How

How was this change accomplished?

Scope

• [ ] significant change to core configuration
• [ ] independent bonus guide
• [ ] simple bug fix

Fixes # (link issue)

Test & maintenance

How can the changes be tested? Is there ongoing maintenance effort? If this is a bonus guide: are you willing to update it from time to time?

Animated GIF (optional)

Add some snazz if you feel like it :)

[twofaktor]

Good catch! Let's go to the main! thanks!