Update federation config, increase default timeline days falloff to 90 days from 2 days. Fixes #4905

config/federation.php

@@ -49,7 +49,7 @@ return [
     ],
 
     'network_timeline' => env('PF_NETWORK_TIMELINE', true),
-    'network_timeline_days_falloff' => env('PF_NETWORK_TIMELINE_DAYS_FALLOFF', 2),
+    'network_timeline_days_falloff' => env('PF_NETWORK_TIMELINE_DAYS_FALLOFF', 90),
 
     'custom_emoji' => [
         'enabled' => env('CUSTOM_EMOJI', false),