ya build: increase memory to 256gb for runner

.github/workflows/build_and_test_ya_ondemand.yml

@@ -52,7 +52,7 @@ jobs:
           disk-size: ${{ vars.DISK_SIZE && vars.DISK_SIZE || '1023GB' }}
           disk-type: network-ssd-nonreplicated
           cores: 32
-          memory: 128GB
+          memory: 256GB
           core-fraction: 100
           zone-id: ru-central1-b
           subnet-id: ${{ secrets.YC_SUBNET }}