[feature] Add ability to parameterize container images

[HumairAK]

Feature Area

/area sdk

What feature would you like to see?

As a user of KFP sdk I want to be able to provide container images as pipeline parameters.

What is the use case or pain point?

There are a number of use cases for this, one example might be requiring a specific image for a specific accelerator type. Having to create multiple pipelines just for different container images is unnecessarily redundant.

Is there a workaround currently?

No

Also note this is a regression from v1.

Previous discussion on this topic: #5834
It was decided not to add this for v2 due to technical hurdles and concerns around component interface breaking. Let's re-evaluate.

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[HumairAK]

I'm thinking we do something like this:

@dsl.component(base_image="docker.io/python:3.9.17")
def empty_component():
    pass

@dsl.pipeline(name='pipeline-accel')
def pipeline_accel(img: str):
    task = empty_component()
    task.set_container_image(img) # overwrite base_image="docker.io/python:3.9.17"

Which would require us to treat the container spec image as a pipeline channel

It looks like we can just follow the same pattern we have followed for setting accelerators

pipelines/sdk/python/kfp/compiler/pipeline_spec_builder.py

Line 618 in 64e3900

def convert_to_placeholder(input_value: str) -> str:

seems pretty straight forward