Add reclient_metrics command

This adds reclient_metrics and reclient_metrics.bat to make it easier
to run reclient_metrics.py. In particular this lets the script be run
without caring about its location and without (on Windows) having to
prefix the script with "python3". This slightly simplifies the reclient
instructions.

Bug: None
Change-Id: Ied58f452edb13cf257873ddee043817a765eee3c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/4764130
Auto-Submit: Bruce Dawson <brucedawson@chromium.org>
Reviewed-by: Ben Segall <bentekkie@google.com>
Commit-Queue: Scott Lee <ddoman@chromium.org>
Reviewed-by: Scott Lee <ddoman@chromium.org>

reclient_metrics

@@ -0,0 +1,8 @@
+#!/usr/bin/env bash
+
+# Copyright 2023 The Chromium Authors
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+base_dir=$(dirname "$0")
+PYTHONDONTWRITEBYTECODE=1 exec python3 "$base_dir/reclient_metrics.py" "$@"

reclient_metrics.bat

@@ -0,0 +1,12 @@
+@echo off
+:: Copyright 2023 The Chromium Authors
+:: Use of this source code is governed by a BSD-style license that can be
+:: found in the LICENSE file.
+setlocal
+
+:: Ensure that "depot_tools" is somewhere in PATH so this tool can be used
+:: standalone, but allow other PATH manipulations to take priority.
+set PATH=%PATH%;%~dp0
+
+:: Defer control.
+python3 "%~dp0\reclient_metrics.py" "%*"