Make acquireVsCodeApi available on global objects

[msujew]

What it does

Closes #13374

Aligns our implementation of the acquireVsCodeApi method to vscode, which is also available on the globalThis and window objects.

How to test

1. Open a webview and hit a breakpoint within
2. Run these scripts in the browsers debugger:

globalThis.acquireVsCodeApi()
window.acquireVsCodeApi()
acquireVsCodeApi()

3. All of them should return the vscode API object.

Review checklist

• As an author, I have thoroughly tested my changes and carefully followed the review guidelines

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