[calls] metainfo: Remove "developer_name" tag

[Evangelos Ribeiro Tzaras <devrtz src gnome org>]

commit f966046c9a1bd0d3ea89e8e2616b0024def593b3
Author: Evangelos Ribeiro Tzaras <devrtz fortysixandtwo eu>
Date:   Tue Oct 19 18:14:20 2021 +0200

    metainfo: Remove "developer_name" tag
    
    `appstreamcli` complains about the tag being duplicated and we are not losing
    anything since credit is given in all the license headers.

 data/org.gnome.Calls.metainfo.xml | 3 ---
 1 file changed, 3 deletions(-)
---
diff --git a/data/org.gnome.Calls.metainfo.xml b/data/org.gnome.Calls.metainfo.xml
index 8b105fd0..436f9a9f 100644
--- a/data/org.gnome.Calls.metainfo.xml
+++ b/data/org.gnome.Calls.metainfo.xml
@@ -14,9 +14,6 @@
     <url type="bugtracker">https://gitlab.gnome.org/GNOME/calls/issues</url>
     
     <project_group>GNOME</project_group>
-    <developer_name>Bob Ham</developer_name>
-    <developer_name>Evangelos Ribeiro Tzaras</developer_name>
-    <developer_name>Julian Sparber</developer_name>
 
     <screenshots>
       <screenshot type="default">