Safely access "num_moe_experts"

Signed-off-by: Piotr Kamiński <67481570+Laplasjan107@users.noreply.github.com>

nemo/export/tensorrt_llm.py

@@ -371,7 +371,7 @@ def export(
                     )
 
                     # TODO: Temporary fix
-                    if model_configs["num_moe_experts"] in {None, 0}:
+                    if model_configs.get("num_moe_experts", None) in {None, 0}:
                         model_configs["num_moe_experts"] = 1
 
                     # We build the transformer config using the nemo model config.