[MM-62133] Activate crossteam search by default (#30348)

* activate cross team search by default

* fix e2e test

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

server/public/model/feature_flags.go

@@ -82,7 +82,7 @@ func (f *FeatureFlags) SetDefaults() {
 	f.WebSocketEventScope = true
 	f.NotificationMonitoring = true
 	f.ExperimentalAuditSettingsSystemConsoleUI = false
-	f.ExperimentalCrossTeamSearch = false
+	f.ExperimentalCrossTeamSearch = true
 	f.CustomProfileAttributes = false
 }