Account for docker buildx using OCI Image Indexes to store layer blobs

Related to: #404 (closed)

added Category:Container Registry backend devopspackage golang grouppackage registry sectionops labels

@jdrpereira threw together this fix for the GC before my long weekend. Only tested this locally, but I think inspecting the media types like this is our option. Threw in some new logging as well.

How do you feel about this approach?

assigned to @hswimelar

mentioned in issue #407 (closed)

added 4 commits

• 5d17693d - Add util to upload buildx cache image
• 55dfa24f - Add manifestlist compat code
• 72785cc9 - Add test for cache manifests
• 12d5c5fc - use compat references in garbage collector

Compare with previous version

added 1 commit

• 8f3c5fdb - remove unused var

Compare with previous version

@hswimelar, this LGTM. Left a few suggestions.

added 1 commit

• 0f8a0a42 - Apply 1 suggestion(s) to 1 file(s)

Compare with previous version

marked this merge request as ready

added 1 commit

• 945c6466 - use blobs instead of layers

Compare with previous version

resolved all threads

enabled an automatic merge when the pipeline for 945c6466 succeeds

mentioned in commit aca86ccb

merged

mentioned in issue #404 (closed)

changed milestone to %14.1

mentioned in merge request !641 (merged)

mentioned in issue #409 (closed)

mentioned in merge request gitlab-com/www-gitlab-com!86124 (merged)

mentioned in merge request !1358 (merged)