testplans: Remove old oneof-style "test_unit" field

This is no longer in use in recipes and it soon will be gone from
the test planner (https://crrev.com/c/1613772).

BUG=chromium:963016
TEST=generate.sh

Change-Id: Ic235aea0717ff8791c35992bade784a9e0261092
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/infra/proto/+/1613773
Reviewed-by: David Burger <dburger@chromium.org>
Commit-Queue: Sean Abraham <seanabraham@chromium.org>
Tested-by: Sean Abraham <seanabraham@chromium.org>
2 files changed
tree: dbdba854cc90d3b6c8d1ddbec61cd6987f33f3da
  1. go/
  2. infra/
  3. recipes/
  4. src/
  5. .gitattributes
  6. .gitignore
  7. generate.sh
  8. LICENSE
  9. OWNERS