I#1824 - Composer: Preserve STYLE element of the signature

And drop TITLE, if it exists.

Closes https://gitlab.gnome.org/GNOME/evolution/-/issues/1824

data/webkit/e-editor.js

@@ -5080,7 +5080,7 @@ EvoEditor.removeUnwantedTags = function(parent)
 	for (child = parent.firstChild; child; child = next) {
 		next = child.nextSibling;
 
-		if (child.tagName == "STYLE" ||
+		if (child.tagName == "TITLE" ||
 		    child.tagName == "META")
 			child.remove();
 	}