ESP32: Fix building chip_gn for cmake v3.31.x and onwards

remove the WORKING_DIRECTORY from chip_gn target

till cmake v3.30, COMMAND in generated build.ninja do not prepend the
WORKING_DIRECTORY path. But, in v3.31 it starts to prepend that path and
build breaks when executing chip_gn step.

command generated for chip_gn-build
For v3.31.x
  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 v3.30.x
  COMMAND = cd /Users/account/esp-matter/examples/light/build/esp-idf/chip && ninja esp32

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
 )