[Editorial] add closing quote missing from original source

A bit of a guess as to where this should go, but I think this makes the most sense.

src/epub/text/chapter-16.xhtml

@@ -76,7 +76,7 @@
 			<p>“But why isn’t he back yet?”</p>
 			<p>“I admit that it’s alarming. Perhaps the man who was following him has attacked him. Or perhaps something has happened to the lady.”</p>
 			<p>“What do you mean, something happened to the lady?”</p>
-			<p>“I’m afraid something may have. When he first showed me the way we should have to go to fetch her, he said, ‘Quick, we must hurry. To save her life, I had to put her in a hole. That’s all very well for two or three hours. But, if she’s left longer, she will suffocate. The want of air⁠ ⁠…”</p>
+			<p>“I’m afraid something may have. When he first showed me the way we should have to go to fetch her, he said, ‘Quick, we must hurry. To save her life, I had to put her in a hole. That’s all very well for two or three hours. But, if she’s left longer, she will suffocate. The want of air⁠ ⁠…’ ”</p>
 			<p>Patrice had leapt upon the old man. He was beside himself, maddened at the thought that Coralie, ill and worn-out as she was, might be at the point of death in some unknown place, a prey to terror and suffering.</p>
 			<p>“You shall speak,” he cried, “and this very minute! You shall tell us where she is! Oh, don’t imagine that you can fool us any longer! Where is she? You know! He told you!”</p>
 			<p>He was shaking <abbr>M.</abbr> Vacherot by the shoulders and hurling his rage into the old man’s face with unspeakable violence.</p>