Hotfix replica sync needs flushing

internal/server/follow.go

@@ -129,6 +129,9 @@ func (c *Server) followHandleCommand(args []string, followc int, w io.Writer) (i
 	if err := c.writeAOF(args, &d); err != nil {
 		return c.aofsz, err
 	}
+	if len(c.aofbuf) > 10240 {
+		c.flushAOF()
+	}
 	return c.aofsz, nil
 }
 
@@ -238,6 +241,7 @@ func (c *Server) followStep(host string, port int, followc int) error {
 			if aofsz >= int(aofSize) {
 				caughtUp = true
 				c.mu.Lock()
+				c.flushAOF()
 				c.fcup = true
 				c.fcuponce = true
 				c.mu.Unlock()