Skip test_show_chassis_modules.py on T2 single node (sonic-net#19199)

Signed-off-by: Guy Shemesh <gshemesh@nvidia.com>

Author: patrickmacarthur

tests/common/plugins/conditional_mark/tests_mark_conditions_platform_tests.yaml

@@ -891,6 +891,21 @@ platform_tests/broadcom/test_ser.py:
     conditions:
       - "release in ['202412','202503'] and 'Arista-7060X6' in hwsku"
 
+##############################################
+#####  cli/test_show_chassis_modules.py  #####
+##############################################
+platform_tests/cli/test_show_chassis_modules.py::test_show_chassis_module_midplane_status:
+  skip:
+    reason: "Not supported on T2 single node topology"
+    conditions:
+      - "'t2_single_node' in topo_name"
+
+platform_tests/cli/test_show_chassis_modules.py::test_show_chassis_module_status:
+  skip:
+    reason: "Not supported on T2 single node topology"
+    conditions:
+      - "'t2_single_node' in topo_name"
+
 #######################################
 #####  cli/test_show_platform.py  #####
 #######################################