Fix flaky integration test

[karlaspuldaro]

Fixes #2638

What changes were proposed in this pull request?

Remove the original work around of adding a new line to the text editor.
Add esc type command to dismiss the code assistant.

How was this pull request tested?

Run script editor tests passes locally and should also pass CI.

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[ajbozarth]

LGTM, just one non-blocking question about the wait length