touch_updater: Update touch firmware report docs report_updater_version

Updated touch_fw_report.md to include info about the
"report_tool_version" utility.

Changed the "report_tool_version" JSON field "version"
to "tool_version".

BUG=b:397567795
TEST=CQ

Change-Id: Ibbecc9694dc08e941f48cf31676cf9e6c1d40b15
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/touch_updater/+/6580172
Tested-by: Hamed A. Elgizery <hamedashraf2004@gmail.com>
Reviewed-by: Henry Barnor <hbarnor@chromium.org>
Reviewed-by: Jingyuan Liang <jingyliang@chromium.org>
Commit-Queue: Hamed A. Elgizery <hamedashraf2004@gmail.com>