[MM-48014] Auto-enable Apps Bar by moving EnableAppBar setting to DisableAppBar (#23010)

* auto-enable Apps Bar by moving EnableAppBar setting to DisableAppBar

* update playwright config

* remove EnableAppBar config setting to avoid confusion

* small fixes

---------

Co-authored-by: Mattermost Build <build@mattermost.com>
Co-authored-by: Harrison Healey <harrisonmhealey@gmail.com>

server/public/model/config.go

@@ -996,7 +996,7 @@ type ExperimentalSettings struct {
 	UseNewSAMLLibrary               *bool   `access:"experimental_features,cloud_restrictable"`
 	EnableSharedChannels            *bool   `access:"experimental_features"`
 	EnableRemoteClusterService      *bool   `access:"experimental_features"`
-	EnableAppBar                    *bool   `access:"experimental_features"`
+	DisableAppBar                   *bool   `access:"experimental_features"`
 	DisableRefetchingOnBrowserFocus *bool   `access:"experimental_features"`
 	DelayChannelAutocomplete        *bool   `access:"experimental_features"`
 }
@@ -1030,8 +1030,8 @@ func (s *ExperimentalSettings) SetDefaults() {
 		s.EnableRemoteClusterService = NewBool(false)
 	}
 
-	if s.EnableAppBar == nil {
-		s.EnableAppBar = NewBool(false)
+	if s.DisableAppBar == nil {
+		s.DisableAppBar = NewBool(false)
 	}
 
 	if s.DisableRefetchingOnBrowserFocus == nil {