.git suffix is not well supported by the systems that utilize
submodules. Since some tools expect DEPS to have .git suffix, it's not
possible to simply update DEPS without breaking the tools.
This patch updates `gclient gitmodules` to omit .git suffix and trailing
slashes. However, if `.gitmodule` already exists, we are expecting the
tool to generate the same result if DEPS didn't change.
R=aravindvasudev@google.com
Bug: b/303296048
Change-Id: I30497b9d5f4e9681e16b4a913151de0f4a7c9545
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/5008942
Reviewed-by: Aravind Vasudevan <aravindvasudev@google.com>
Commit-Queue: Josip Sokcevic <sokcevic@chromium.org>
