ESP32: Fix building chip_gn for cmake v3.31.x and onwards (#36606)

remove the WORKING_DIRECTORY from chip_gn target

For cmake v3.31.x, custom command generated for chip_gn-build in
build.ninja concats the $WORKING_DIRECTORY and $BUILD_DIR paths and
it mess up the chip_gn step when building example.
    COMMAND = cd "/Users/account/esp-matter/connectedhomeip/connectedhomeip/config/esp32/components/chip;/Users/account/esp-matter/examples/light/build/esp-idf/chip" && ninja esp32

For cmake version prior to v3.31, it do not prepend the
$WORKING_DIRECTORY path.
    COMMAND = cd /Users/account/esp-matter/examples/light/build/esp-idf/chip && ninja esp32

This could be becuase of Kitware/CMake@f5f8030

related issue - espressif/esp-matter#1157

config/esp32/components/chip/CMakeLists.txt

@@ -389,7 +389,6 @@ externalproject_add(
     BUILD_COMMAND           ninja "esp32"
     INSTALL_COMMAND         ""
     BUILD_BYPRODUCTS        ${chip_libraries}
-    WORKING_DIRECTORY       ${CMAKE_CURRENT_LIST_DIR}
     DEPENDS                 args_gn
     BUILD_ALWAYS            1
 )