Photos: Update base styles to match Gutenberg styles

`blockquote cite` wasn't meant to be bold, but I missed this in testing because you can't add a `cite` tag in TinyMCE without doing it manually.

photos/style.css

@@ -440,8 +440,9 @@ blockquote *:last-child {
 }
 
 blockquote cite {
+	color: #606060;
 	font-style: normal;
-	font-weight: bold;
+	font-weight: 300;
 }
 
 address {