chore: update app description

appinfo/info.xml

@@ -8,9 +8,9 @@
     <id>files_emailviewer</id>
     <name>Email Viewer</name>
     <summary>View .msg and .eml files</summary>
-    <description><![CDATA[## Email Viewer integrates the excellent Email to PDF Converter into Nextcloud, enabling you to view .msg and .eml files.
+    <description><![CDATA[### Email Viewer integrates the excellent Email to PDF Converter into Nextcloud, enabling you to view .msg and .eml files.
 
-### Requirements
+#### Requirements
 
 - Nextcloud 28 or newer
 - PDF Viewer for Nextcloud
@@ -19,14 +19,14 @@
 - [wkhtmltopdf](https://wkhtmltopdf.org/)
 - [Email to PDF Converter](https://github.com/nickrussler/email-to-pdf-converter)
 
-### Installation
+#### Installation
 
 - Download and enable files_emailviewer
 - Store a copy of the Email to PDF Converter on the server, ensuring that Nextcloud has access to it
 - Set the path to Email to PDF Converter via `occ config:app:set --value /opt/emailconverter-3.0.0-all.jar files_emailviewer binary_path`
 - Upload a .msg or .eml file and view it directly in Nextcloud 🙌
 
-### Outgoing connections
+#### Outgoing connections
 
 - If the email contains images from external sources, the Email to PDF converter will download the images, requiring external connections
 - The current version does not consider Nextcloud's proxy configuration but should follow the system default