Fix plotly hanging while rendering bug (#7359)

Addresses #6033

The problem that was occurring was that the webview was attempted to be
opened with no extension. However, the extension object sent over looked
like `{id: undefined}`, so when it was being unpacked by the webview
class it checked if the id field exists, and then once it sees it _does_
it assumes we have a full id object, which we don't. Thus it was trying
to pick off value from `undefined`. This PR simply adds one more
optional chaining step for the accessing of `value` on the id. This
fixed the error in my setup.



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#### New Features

- N/A

#### Bug Fixes

- Fix plotly hanging while rendering bug. 


### QA Notes

- Run the following code: 
```python
import plotly.express as px
fig = px.bar(x=["a", "b", "c"], y=[1, 3, 2])
fig
```
and you should get a plot and a nice and not frozen console.

Author: nstrayer

src/vs/workbench/contrib/webview/browser/webviewElement.ts

@@ -478,7 +478,7 @@ export class WebviewElement extends Disposable implements IWebview, WebviewFindD
 			id: this.id,
 			origin: this.origin,
 			swVersion: String(this._expectedServiceWorkerVersion),
-			extensionId: extension?.id.value ?? '',
+			extensionId: extension?.id?.value ?? '',
 			platform: this.platform,
 			'vscode-resource-base-authority': webviewRootResourceAuthority,
 			parentOrigin: targetWindow.origin,