Revert PR#16537 (MystenLabs#16559)

simtests are no longer immediately after
[MystenLabs#16537](MystenLabs#16537) :

https://github.com/MystenLabs/sui/actions/runs/8160893924/job/22308495694

scripts/simtest/cargo-simtest

@@ -75,16 +75,6 @@ if [ -n "$USE_MOCK_CRYPTO" ]; then
   )
 fi
 
-TARGET=$(rustc -vV | grep host | sed 's/^host: //')
-if [ -z "$TARGET" ]; then
-  echo "Failed to determine target from rustc -vV"
-  exit 1
-fi
-
-# set target so that cargo runs in cross compilation mode. needed so that build
-# scripts are not built with the simulator
-export CARGO_BUILD_TARGET="$TARGET"
-
 RUST_FLAGS=$(IFS=, ; echo "${RUST_FLAGS[*]}")
 
 if ! cargo nextest --help > /dev/null 2>&1; then