[nrf fromlist][cmake] Fix building issue due to lack of Python3 under Windows

This commit ensures that ${Python3_EXECUTABLE} is used when executing
codegen_paths.py script.

Upstream PR #: 40425

Signed-off-by: Łukasz Duda <[email protected]>

Author: LuDuda

build/chip/chip_codegen.cmake

@@ -33,12 +33,15 @@ function(chip_codegen TARGET_NAME)
 
     set(CHIP_CODEGEN_PREGEN_DIR "" CACHE PATH "Pre-generated directory to use instead of compile-time code generation.")
 
+    # Python is required for code generation
+    find_package(Python3 REQUIRED)
+
     # Output paths can contain placeholders such as
     # {{defined_cluster_name}} or {{server_cluster_name}}
     #
     # This translates them to the actually fully expanded path.
     execute_process(
-            COMMAND "${CHIP_ROOT}/scripts/codegen_paths.py" "--idl" "${ARG_INPUT}" ${ARG_OUTPUTS}
+            COMMAND "${Python3_EXECUTABLE}" "${CHIP_ROOT}/scripts/codegen_paths.py" "--idl" "${ARG_INPUT}" ${ARG_OUTPUTS}
             OUTPUT_VARIABLE GENERATED_PATHS_OUT
     )
     string(REPLACE "\n" ";" GENERATED_PATHS "${GENERATED_PATHS_OUT}")
@@ -60,12 +63,9 @@ function(chip_codegen TARGET_NAME)
             list(APPEND OUT_NAMES "${GEN_FOLDER}/${NAME}")
         endforeach()
 
-        # Python is expected to be in the path
-        #
-        find_package(Python3 REQUIRED)
         add_custom_command(
             OUTPUT ${OUT_NAMES}
-            COMMAND ${Python3_EXECUTABLE} "${CHIP_ROOT}/scripts/codegen.py"
+            COMMAND "${Python3_EXECUTABLE}" "${CHIP_ROOT}/scripts/codegen.py"
             ARGS "--generator" "${ARG_GENERATOR}"
                  "--output-dir" "${GEN_FOLDER}"
                  "--expected-outputs" "${GEN_FOLDER}/expected.outputs"