Yes, you absolutely can eat it, but eat in moderation. Make sure the vegetables are washed properly and the milk/cheese used is fully cooked. Avoid street-side or unhygienic places, home-cooked pasta is the safest bet.
I used to crave white sauce pasta so much during my pregnancy! I always made it at home with lots of veggies like broccoli and mushrooms to make it slightly healthy. Just enjoy your food but try to avoid too much outside food to keep your stomach safe.
I totally understand your fear, I used to google literally every single ingredient before putting it in my mouth! You can definitely have white sauce pasta, just ensure the cheese is pasteurized. Take a deep breath, it is completely safe to indulge sometimes.
Haha go eat it, yaara! Baby is also probably craving some cheese in there. Just make sure the cheese is pasteurized and you don't eat the whole pan, otherwise heartburn will keep you awake all night!
Honestly, I had white sauce pasta like once every week in my last trimester and my baby is perfectly fine. Just make sure it is served hot and the cheese is melted well. If u are ordering from outside, choose a good hygienic restaurant.