Remove Alphaplan stage

We do not use Alphaplan anymore. Remove everything Alphaplan related stuff from the pipeline.

merged

Integration merge request: https://git.seco.com/seco-ne/yocto/infrastructure/ci-test/minimal-srcrev/-/merge_requests/140

Integration merge request: https://git.seco.com/seco-ne/yocto/infrastructure/ci-test/minimal-foo/-/merge_requests/397

Integration merge request: https://git.seco.com/seco-ne/yocto/infrastructure/ci-test/minimal-bar/-/merge_requests/296

Integration merge request: https://git.seco.com/seco-ne/yocto/infrastructure/ci-test/minimal-foo/-/merge_requests/398

Integration merge request: https://git.seco.com/seco-ne/yocto/infrastructure/ci-test/minimal-manifest/-/merge_requests/661

Integration merge request: https://git.seco.com/seco-ne/yocto/infrastructure/ci-test/minimal-manifest/-/merge_requests/662

Integration merge request: seco-ne/kernel/modules/gfplatdetect!100 (merged)

mentioned in merge request seco-ne/kernel/modules/gfplatdetect!100 (merged)

Integration merge request: seco-ne/kernel/modules/egalaxi2c!103 (merged)

mentioned in merge request seco-ne/kernel/modules/egalaxi2c!103 (merged)

Integration merge request: seco-ne/kernel/linux-guf!261 (merged)

mentioned in merge request seco-ne/kernel/linux-guf!261 (merged)

Integration merge request: seco-ne/kernel/linux-imx-kuk!413 (merged)