Deploy swh.loader.git v2.6

Contains:

• improved git directory loader (faster and compute correctly hash trees)

Common:

• Fix swh-lister app build [2]
• swh/devel/swh-loader-metadata!17 (merged): Fix swh-apps builds which are broken due to an extra deps on swh-lister (with a new rpy2 deps) [1]
• swh/devel/swh-lister!499 (merged): swh-lister: Clean up
• swh-lister: probably debian build to fix (nope it seems to work already ;)

staging:

• swh-charts: Build new images
• argocd: Deploy new version
• Checks (does the git checkout queue subside now?)

production:

• merge staging branch
• Checks (other git, save-code-now, add-forge-now should run as usual)

[1] https://jenkins.softwareheritage.org/job/swh-apps/job/build-docker-image/518/console (among other things)

[2] https://jenkins.softwareheritage.org/job/swh-apps/job/build-docker-image/522