Download amd64 Goma client regardless of arch.

There is a case that people use 32bit shell on 64bit OSes.
Since Goma client cipd package is made only on amd64, people who
use i386 cannot use Goma cipd packages.
To allow such a case to use Goma, let me make amd64 Goma client
installed regardless of the current architecture.

Bug: b/158498375
Change-Id: I2ccc9411e41894e0031b943123bfac45f74c24a0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/2240985
Auto-Submit: Yoshisato Yanagisawa <yyanagisawa@chromium.org>
Commit-Queue: Fumitoshi Ukai <ukai@google.com>
Reviewed-by: Simon Que <sque@chromium.org>
Reviewed-by: Fumitoshi Ukai <ukai@google.com>

cipd_manifest.txt

@@ -57,4 +57,4 @@ infra/tools/rdb/${platform} git_revision:79cb205f7d21a49375a9721bec780770a2296f3
 chromiumos/infra/crosjobs/${platform=linux-amd64} git_revision:ed616d595eb7241d39d34907050d2949121d6ae8
 
 # goma client
-infra/goma/client/${os}-${arch=amd64} git_revision:80401d72a6476494ab19ac9bed48a6cccbd6f8e0
+infra/goma/client/${os}-amd64 git_revision:80401d72a6476494ab19ac9bed48a6cccbd6f8e0