The playground on the landing page is completely broken

If I go to https://jmespath.org/ and type something in, nothing happens. If I press enter, the entire page reloads and resets to the original example.

Additionally, I see a lot of errors in the devtools console.

```
Uncaught ParserError: Expected Star, got: Literal
V https://jmespath.org/_static/js/jmespath.min.js:2
led https://jmespath.org/_static/js/jmespath.min.js:2
expression https://jmespath.org/_static/js/jmespath.min.js:2
parse https://jmespath.org/_static/js/jmespath.min.js:2
p https://jmespath.org/_static/js/jmespath.min.js:2
evaluateDemo https://jmespath.org/:144
https://jmespath.org/:153
jQuery x2
https://jmespath.org/:140
jQuery x11
jmespath.min.js:2:8945
```