[evolution] help: Fix a typo

[Andre Klapper <aklapper src gnome org>]

commit b0945a04d38152f821b5a7027da602aea6bb1457
Author: Andre Klapper <a9016009 gmx de>
Date:   Sat Apr 10 11:42:39 2021 +0200

    help: Fix a typo

 help/C/mail-displaying-message.page | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/help/C/mail-displaying-message.page b/help/C/mail-displaying-message.page
index a536445af1..c79aa849b8 100644
--- a/help/C/mail-displaying-message.page
+++ b/help/C/mail-displaying-message.page
@@ -20,7 +20,7 @@
 
 <title>Display of a message</title>
 
-<p>Emails can be in two formats: <link xref="https://en.wikipedia.org/wiki/Email#Plain_text_and_HTML";>Plain 
text or HTML</link>. Each format has its pros and cons.</p>
+<p>Emails can be in two formats: <link href="https://en.wikipedia.org/wiki/Email#Plain_text_and_HTML";>Plain 
text or HTML</link>. Each format has its pros and cons.</p>
 
 <p>You can define how received HTML messages are displayed via 
<guiseq><gui>Edit</gui><gui>Preferences</gui><gui>Mail Preferences</gui><gui>HTML Messages</gui></guiseq>. 
For example, you can display them as plain text or block loading remote content.</p>