Better handling for changed dimensions

[KaelWD]

Currently it overwrites the baseline instead of failing:

cli/src/tdd/tdd-service.js

Lines 1420 to 1426 in 16dc2ff

	if (isDimensionMismatchError(error)) {
	output.debug(
	'comparison',
	`${sanitizedName}: dimension mismatch, creating new baseline`
	);
	saveBaseline(this.baselinePath, filename, imageBuffer);

If it isn't possible to generate a diff for some reason we should still be able to compare them side by side.