Update spec test cases to latest version (#889)

Update spec test cases to commit 2460ad02b51fb5ed5824f44de287a8638b19a5f8,
and modify wamr test suite script as the SIMD cases have been added into spec
main repo by default, no need to clone SIMD repo again when testing SIMD.

core/iwasm/interpreter/wasm_loader.c

@@ -3342,6 +3342,7 @@ create_sections(const uint8 *buf, uint32 size, WASMSection **p_section_list,
                 if (last_section_index != (uint8)-1
                     && (section_index <= last_section_index)) {
                     set_error_buf(error_buf, error_buf_size,
+                                  "unexpected content after last section or "
                                   "junk after last section");
                     return false;
                 }