Fix typo in morphisms

Thanks to Zhaodong Cai
https://stacks.math.columbia.edu/tag/0CNG#comment-4726

Author: aisejohan

CONTRIBUTORS

@@ -39,6 +39,7 @@ Elyes Boughattas
 Ragnar-Olaf Buchweitz
 Kevin Buzzard
 Jakub Byszewski
+Zhaodong Cai
 Nicholas Camacho
 Samir Canning
 Robert Cardona

morphisms.tex

@@ -1003,7 +1003,7 @@ \section{Scheme theoretic image}
 (Topology, Definition \ref{topology-definition-quasi-compact})
 means that $V \to Y$ is a quasi-compact morphism.
 By Schemes, Lemma \ref{schemes-lemma-quasi-compact-permanence}
-the morphism $s : V \to Y$ is quasi-compact.
+the morphism $s : V \to X$ is quasi-compact.
 Hence the construction of the scheme theoretic image $Y'$
 of $s$ commutes with restriction to opens by
 Lemma \ref{lemma-quasi-compact-scheme-theoretic-image}.