bigcup -> bigoplus

THanks to Ben Moonen
https://stacks.math.columbia.edu/tag/08XV#comment-7771

dualizing.tex

@@ -296,13 +296,13 @@ \section{Injective modules}
 
 \begin{proof}
 Let $E_i$ be a family of injective modules parametrized by a set $I$.
-Set $E = \bigcup E_i$. To show that $E$ is injective we use
+Set $E = \bigoplus E_i$. To show that $E$ is injective we use
 Injectives, Lemma \ref{injectives-lemma-criterion-baer}.
 Thus let $\varphi : I \to E$ be a module map from an ideal of $R$
 into $E$. As $I$ is a finite $R$-module (because $R$ is Noetherian)
 we can find finitely many elements $i_1, \ldots, i_r \in I$
-such that $\varphi$ maps into $\bigcup_{j = 1, \ldots, r} E_{i_j}$.
-Then we can extend $\varphi$ into $\bigcup_{j = 1, \ldots, r} E_{i_j}$
+such that $\varphi$ maps into $\bigoplus_{j = 1, \ldots, r} E_{i_j}$.
+Then we can extend $\varphi$ into $\bigoplus_{j = 1, \ldots, r} E_{i_j}$
 using the injectivity of the modules $E_{i_j}$.
 \end{proof}