MM-54181 : Clean up code around deprecated Gfycat (#24343)

* first pass of removal

* first pass of removal

* Update admin_console.js

* rev beta

* remove more

* Update initial_state.ts

---------

Co-authored-by: Mattermost Build <build@mattermost.com>

server/config/diff.go

@@ -53,7 +53,6 @@ var configSensitivePaths = map[string]bool{
 	"MessageExportSettings.GlobalRelaySettings.SMTPUsername": true,
 	"MessageExportSettings.GlobalRelaySettings.SMTPPassword": true,
 	"MessageExportSettings.GlobalRelaySettings.EmailAddress": true,
-	"ServiceSettings.GfycatAPISecret":                        true,
 	"ServiceSettings.SplitKey":                               true,
 	"PluginSettings.Plugins":                                 true,
 }