fix(FormControl): handle props spreading properly

[huyenltnguyen]

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We're passing the combined class names (default + custom) to the component, but the default class names are overridden by the custom className because we're spreading the entire props object after that.

ui/src/form-control/form-control.tsx

Lines 25 to 27 in db06a09

	const classes = [className, defaultClasses, variantClass].join(" ");
	return <Component id={id || controlId} className={classes} {...props} />;