Question about the behavior of content script.

### What is this about?

I was wondering why it clears the script tag when I inject.
I'm wondering if there's something wrong with it?

https://github.com/MetaMask/metamask-extension/blob/a3a99aaaebc1a5b7edae6678a8452dd72b887441/app/scripts/contentscript.js#L79

```js
function injectScript(content) {
try {
const container = document.head || document.documentElement;
const scriptTag = document.createElement('script');
scriptTag.setAttribute('async', 'false');
scriptTag.textContent = content;
container.insertBefore(scriptTag, container.children[0]);
container.removeChild(scriptTag);
} catch (error) {
console.error('MetaMask: Provider injection failed.', error);
}
}
```

### Scenario

_No response_

### Design

_No response_

### Technical Details

_No response_

### Threat Modeling Framework

_No response_

### Acceptance Criteria

_No response_

### References

_No response_

Start with app/scripts/contentscript.js at line 79 and read the surrounding injectScript function. Trace how the injected content is used and determine whether removing the script tag is expected; document the explanation or identify a concrete behavior that needs changing.

Written by the indexing model from the issue text.