MM-49048: do not omit needed wsbroadcast vars (#22156)

* MM-49048: do not omit needed wsbroadcast vars

It seems that we are omitting ContainsSanitizedData, and
ContainsSensitiveData variables in WebsocketBroadcast.
This created a bug in cluster mode, in which we were sending duplicate
events to users whereas normally they would have access to only one of those.

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

model/websocket_message.go

@@ -91,14 +91,14 @@ type WebSocketMessage interface {
 }
 
 type WebsocketBroadcast struct {
-	OmitUsers             map[string]bool `json:"omit_users"`         // broadcast is omitted for users listed here
-	UserId                string          `json:"user_id"`            // broadcast only occurs for this user
-	ChannelId             string          `json:"channel_id"`         // broadcast only occurs for users in this channel
-	TeamId                string          `json:"team_id"`            // broadcast only occurs for users in this team
-	ConnectionId          string          `json:"connection_id"`      // broadcast only occurs for this connection
-	OmitConnectionId      string          `json:"omit_connection_id"` // broadcast is omitted for this connection
-	ContainsSanitizedData bool            `json:"-"`
-	ContainsSensitiveData bool            `json:"-"`
+	OmitUsers             map[string]bool `json:"omit_users"`                        // broadcast is omitted for users listed here
+	UserId                string          `json:"user_id"`                           // broadcast only occurs for this user
+	ChannelId             string          `json:"channel_id"`                        // broadcast only occurs for users in this channel
+	TeamId                string          `json:"team_id"`                           // broadcast only occurs for users in this team
+	ConnectionId          string          `json:"connection_id"`                     // broadcast only occurs for this connection
+	OmitConnectionId      string          `json:"omit_connection_id"`                // broadcast is omitted for this connection
+	ContainsSanitizedData bool            `json:"contains_sanitized_data,omitempty"` // broadcast only occurs for non-sysadmins
+	ContainsSensitiveData bool            `json:"contains_sensitive_data,omitempty"` // broadcast only occurs for sysadmins
 	// ReliableClusterSend indicates whether or not the message should
 	// be sent through the cluster using the reliable, TCP backed channel.
 	ReliableClusterSend bool `json:"-"`