Revert "hotfix: change MAX_JOBS in aot ci (#1621)" (#1629)

This reverts commit 463cd22.

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Author: yzh119

scripts/task_test_aot_build_import.sh

@@ -3,29 +3,14 @@
 set -eo pipefail
 set -x
 
-# Set MAX_JOBS based on architecture and available memory
-ARCH=$(uname -m)
+# MAX_JOBS = min(nproc, max(1, MemAvailable_GB/4))
 MEM_AVAILABLE_GB=$(free -g | awk '/^Mem:/ {print $7}')
 NPROC=$(nproc)
-
-# Calculate base MAX_JOBS based on memory (4GB per job)
-BASE_MAX_JOBS=$(( MEM_AVAILABLE_GB / 4 ))
-if (( BASE_MAX_JOBS < 1 )); then
-  BASE_MAX_JOBS=1
-elif (( NPROC < BASE_MAX_JOBS )); then
-  BASE_MAX_JOBS=$NPROC
-fi
-
-# Apply architecture-specific scaling
-if [[ "$ARCH" == "aarch64" ]]; then
-  # Use half the jobs on aarch64 compared to x86_64
-  MAX_JOBS=$(( BASE_MAX_JOBS / 2 ))
-  if (( MAX_JOBS < 1 )); then
-    MAX_JOBS=1
-  fi
-else
-  # x86_64, amd64, and other architectures use full capacity
-  MAX_JOBS=$BASE_MAX_JOBS
+MAX_JOBS=$(( MEM_AVAILABLE_GB / 4 ))
+if (( MAX_JOBS < 1 )); then
+  MAX_JOBS=1
+elif (( NPROC < MAX_JOBS )); then
+  MAX_JOBS=$NPROC
 fi
 
 # Export MAX_JOBS for PyTorch's cpp_extension to use