Fix a typo in algebra

Thanks to Rankeya
Also addressed a previous comment by Dario Weissmann
https://stacks.math.columbia.edu/tag/0BUF#comment-4890
https://stacks.math.columbia.edu/tag/0BUF#comment-3253

algebra.tex

@@ -30777,10 +30777,9 @@ \section{Colimits and maps of finite presentation}
 
 \begin{proof}
 The category\footnote{To avoid set theoretical difficulties we
-consider only $A' \to A$ such that the underlying set of $A'$
-is a subset of a fixed set of sufficiently large cardinality,
-for example the power set of $A$.}
-$\mathcal{I}$ is nonempty as $R \to A$ is an object of it.
+consider only $A' \to A$ such that $A'$ is a quotient of
+$R[x_1, x_2, x_3, \ldots]$.}
+$\mathcal{I}$ is nonempty as $R \to R$ is an object of it.
 Consider a pair of objects $A' \to A$, $A'' \to A$ of $\mathcal{I}$.
 Then $A' \otimes_R A'' \to A$ is in
 $\mathcal{I}$ (use Lemmas \ref{lemma-compose-finite-type} and