[infra] Add internal_bot_id flag to recipes

Allows differentiation between internal bots in recipes.

Bug: skia:
Change-Id: I7130f2adc13dd01f7572856ea64c428a6adf56ba
Reviewed-on: https://skia-review.googlesource.com/46844
Reviewed-by: Kevin Lubick <kjlubick@google.com>
Commit-Queue: Eric Boren <borenet@google.com>
4 files changed