The modern meaning of the world science is "natural science". Even the article you cite explains that the claim by Gauss that mathematics is a science implies the old meaning of the word.
Still, if this bothers you, replace "science" by "natural science" in my claim and the relevant aspect of the argument remains unchanged.
Still, if this bothers you, replace "science" by "natural science" in my claim and the relevant aspect of the argument remains unchanged.