fix: export test script should use current working directory

The script was changing to its own directory (.github/workflows)
instead of using the current directory where the workflow already
placed it (_demo/embed/export). This caused the script to look for
go.mod in the wrong location.

Fixed by using pwd instead of changing to the script's directory.

Generated with [codeagent](https://github.com/qbox/codeagent)
Co-authored-by: luoliwoshang <51194195+luoliwoshang@users.noreply.github.com>

.github/workflows/export_test.sh

@@ -6,9 +6,8 @@
 
 set -e  # Exit on any error
 
-# Get script directory
-SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
-cd "$SCRIPT_DIR"
+# Use current working directory (workflow already cd's to the test directory)
+WORK_DIR="$(pwd)"
 
 # Colors for output
 RED='\033[0;31m'
@@ -38,7 +37,7 @@ if [[ -z "$LLGO_ROOT" ]]; then
 fi
 
 print_status "Starting export symbol name test..."
-print_status "Working directory: $SCRIPT_DIR"
+print_status "Working directory: $WORK_DIR"
 print_status "LLGO_ROOT: $LLGO_ROOT"
 
 echo ""