[WASM] Use backup option and remove them

Author: kateinoigakukun

utils/webassembly/build-toolchain.sh

@@ -122,9 +122,9 @@ merge_toolchains() {
 
   # Replace absolute sysroot path with relative path
   sed -i.bak -e "s@\".*/include@\"../../../../share/wasi-sysroot/include@g" "$DIST_TOOLCHAIN_SDK/usr/lib/swift/wasi/wasm32/wasi.modulemap"
-  rm "$DIST_TOOLCHAIN_SDK/usr/lib/swift/wasi/wasm32/wasi.modulemap"
+  rm "$DIST_TOOLCHAIN_SDK/usr/lib/swift/wasi/wasm32/wasi.modulemap.bak"
   sed -i.bak -e "s@\".*/include@\"../../../../share/wasi-sysroot/include@g" "$DIST_TOOLCHAIN_SDK/usr/lib/swift_static/wasi/wasm32/wasi.modulemap"
-  rm "$DIST_TOOLCHAIN_SDK/usr/lib/swift_static/wasi/wasm32/wasi.modulemap"
+  rm "$DIST_TOOLCHAIN_SDK/usr/lib/swift_static/wasi/wasm32/wasi.modulemap.bak"
 }
 
 create_darwin_info_plist() {