[chassis][voq] fix for voq fabric related tests (sonic-net#16068)

What is the motivation for this PR?
Fixing issue 16067.

How did you do it?
Changed to not re-write originalIsolateStatus but instead write to isolateStatus.
Also added try/catch block to both tests as today if the test fails it exits without restoring the state of the port.

I also added check to tests/voq/test_fabric_reach.py::test_fabric_reach_supervisor to run against only if asic is present. Right not the tests get the max asics for the platform and assumes they are all present.

How did you verify/test it?
Ran against t2 Nokia chassis

tests/common/plugins/sanity_check/recover.py

@@ -163,10 +163,12 @@ def adaptive_recover(dut, localhost, fanouthosts, nbrhosts, tbinfo, check_result
                 action = _recover_services(dut, result)
             elif result['check_item'] == 'bgp':
                 # If there is only default route missing issue, only need to re-announce routes to recover
-                if ("no_v4_default_route" in result['bgp'] and len(result['bgp']) == 1 or
-                    "no_v6_default_route" in result['bgp'] and len(result['bgp']) == 1 or
+                # Currently only support single asic
+                if (dut.facts["num_asic"] == 1 and
+                    ("no_v4_default_route" in result['bgp'] and len(result['bgp']) == 1 or
+                     "no_v6_default_route" in result['bgp'] and len(result['bgp']) == 1 or
                     ("no_v4_default_route" in result['bgp'] and "no_v6_default_route" in result['bgp'] and
-                     len(result['bgp']) == 2)):
+                     len(result['bgp']) == 2))):
                     action = re_announce_routes(localhost, tbinfo["topo"]["name"], tbinfo["ptf_ip"])
                 else:
                     action = neighbor_vm_restore(dut, nbrhosts, tbinfo, result)