Don't include this function types in completeFunctionCalls

[xuanduc987]

This PR fixes #104877

[mjbvz]

What issue does this fix?

[xuanduc987]

Typescript allow annotating this parameter https://www.typescriptlang.org/docs/handbook/functions.html#this-parameters

function f(this: void) {
  // make sure `this` is unusable in this standalone function
}

Because this parameters are fake parameters, I think we should skip these.

[mjbvz]

Thanks. Can you also create a normal issue to track this problem. This helps us track issues and verify this PR fixed it

[xuanduc987]

I had created #104877 to track this issue. Thanks.

[mjbvz]

Thanks! This will be in the next VS Code insiders build and is scheduled to ship with VS Code 1.49