WIP: Regression on contenteditable

[RaiVaibhav]

Fixes: #5018
Fixes: #5931

The issue caused because of setting the updated value to the data property of mustache text node, use innerText if parent have contenteditable attribute

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Tests

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[RaiVaibhav]

Closing: innerText is a trick that can cause another issue like dom update on text node value change, rather we should add a warning so that developers know that mustache is a text node in case of contenteditable and innerText will not even work in first place.