`String.num` now prints trailing zeroes on whole numbers

**Your Godot version:**
4.4-stable

**Issue description:**
In Godot 4.4, Calling `String.num` with an integer/whole number parameter with no second argument returns a String for that number with a trailing ".0". For example, `String.num(42)` returns `"42.0"`. The docs for `String.num` say that trailing zeroes are not printed.
In 4.3, this was correct, and `String.num(42)` returned `"42"`.

**URL to the documentation page:**
https://docs.godotengine.org/en/4.4/classes/class_string.html#class-string-method-num