ci: Introduce "Build Container (BC)" type
To comply with security requirements, we must rebuild the benchmark containers regularly. We will do this using a gitlab scheduled pipeline. To prepare for that, let's add the concept of a pipeline type via the PIPELINE_TYPE variable. The existing type is now called "Continuous Integration (CI)" and we introduce "Build Container (BC)", which when invoked, will build a specified container tagged with the specified version.
The scheduled pipelines will be setup to invoke this new type.
Signed-off-by: Ryan Roberts ryan.roberts@arm.com