Add revert instructions to .bat and bash files which are the entry
points to various infra tools deployed via CIPD.

Bug: 1206818
Change-Id: Ib0045aea86f29d0f7e3a43c6ff314c4b7aa74171
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/2892387
Auto-Submit: Nodir Turakulov <nodir@chromium.org>
Reviewed-by: Vadim Shtayura <vadimsh@chromium.org>
Reviewed-by: Dirk Pranke <dpranke@google.com>
Reviewed-by: Bruce Dawson <brucedawson@chromium.org>
Commit-Queue: Dirk Pranke <dpranke@google.com>