Revert "Update depot_tools using main branch"

This reverts commit c2c576e9.

Reason for revert: windows zip archived linked in documentation
only fetches master branch, so that needs to resolved first.

Original change's description:
> Update depot_tools using main branch
>
> R=​ehmaldonado@chromium.org
>
> Change-Id: Ie8d00331d649fa33158bb78d0bb64eacd121f044
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/2748935
> Commit-Queue: Josip Sokcevic <sokcevic@google.com>
> Reviewed-by: Edward Lesmes <ehmaldonado@chromium.org>

Change-Id: I873f84f8fbe3a6cde60955ca63eb81e6976dd1f8
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/2748946
Auto-Submit: Josip Sokcevic <sokcevic@google.com>
Commit-Queue: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>

update_depot_tools

@@ -101,7 +101,7 @@ function update_git_repo {
 
   git fetch -q origin &> /dev/null
   local CHECKOUT_TXT STATUS
-  CHECKOUT_TXT=$(git checkout -q origin/main 2>&1)
+  CHECKOUT_TXT=$(git checkout -q origin/master 2>&1)
   STATUS=$?
   if [[ $STATUS -ne 0 ]]; then
     echo "depot_tools update failed. Conflict in $base_dir" >&2

update_depot_tools.bat

@@ -52,7 +52,7 @@ for /F %%x in ('git config --get remote.origin.url') DO (
   )
 )
 call git fetch -q origin > NUL
-call git checkout -q origin/main > NUL
+call git checkout -q origin/master > NUL
 if errorlevel 1 (
   echo Failed to update depot_tools.
   goto :EOF