test/py: Reset the console timeout value

Reset the console timeout value as some tests may change its default
value during the execution.

This fixes the random case timeout issue seen in the U-Boot CI.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>

test/py/u_boot_console_base.py

@@ -400,6 +400,10 @@ class ConsoleBase(object):
         """
 
         if self.p:
+            # Reset the console timeout value as some tests may change
+            # its default value during the execution
+            if not self.config.gdbserver:
+                self.p.timeout = 30000
             return
         try:
             self.log.start_section('Starting U-Boot')