[ResultDB] cmd_stream: Do not fail the task if -location-tags-file does not exist
[ResultDB] cmd_stream: Do not fail the task if -location-tags-file does not exist

Bug: 1103287
Change-Id: I79d2035e7d70a650da34324915106f119ecd27c5
Reviewed-on: https://chromium-review.googlesource.com/c/infra/luci/luci-go/+/2639156
Commit-Queue: Chan Li <332b6c56634d0f63001046c664a2370006a02420@chromium.org>
Reviewed-by: Nodir Turakulov <ef4933a197ef7b4b3f55f1bec4942aead3637a2a@chromium.org>

luci/luci-go,luci/luci-go,luci/luci-go,luci/luci-go,luci/luci-go,luci/luci-go