I actually work in automotive testing, and the honest truth is that there likely is no real automated pipeline.

Automotive software testing is much more complex than simple software unit or integration tests. You need to run on actual hardware, accompanied by all the other ECUs you are interfacing with. And the tools that slow you to do so are specialized tools, which often are not yet integrated into CI/CD processes (they're pretty much all working on it though). I.e. getting test results for a build involves manual labor, which makes it prone to errors.