Add separate method for post validation

Signed-off-by: Partho Sarthi <[email protected]>

user_tools/src/spark_rapids_tools/cmdli/argprocessor.py

@@ -237,11 +237,14 @@ def get_or_set_platform(self) -> CspEnv:
             runtime_platform = CspEnv.get_default()
         else:
             runtime_platform = self.p_args['toolArgs']['platform']
+        self.post_platform_assignment_validation()
+        return runtime_platform
 
-        # Update argv_cases to reflect the platform and validate post platform assignment
+    def post_platform_assignment_validation(self):
+        # Update argv_cases to reflect the platform
         self.argv_cases[0] = ArgValueCase.VALUE_A
+        # Any validation post platform assignment should be done here
         self.apply_arg_cases([self.rejected, self.extra])
-        return runtime_platform
 
 
 @dataclass