pipe just generated file throught rustfmt instead of doing on entire project

compile_and_run.sh

@@ -1,5 +1,4 @@
 #!/bin/bash -x
-python scripts/pism.py proofs/simple.pism > src/simple_circuit.rs
-cargo fmt
+python scripts/pism.py proofs/simple.pism | rustfmt > src/simple_circuit.rs
 cargo run --release --bin simple