Add oppressive language presubmit

BUG=b:162024466
TEST=try to upload a CL with a blocked term

Change-Id: I7f224b2563cbf06f00f069f4c310cb96d10286bb
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/mttools/+/2664794
Tested-by: Harry Cutts <[email protected]>
Auto-Submit: Harry Cutts <[email protected]>
Reviewed-by: Sean O'Brien <[email protected]>
Commit-Queue: Harry Cutts <[email protected]>
1 file changed