Fix image status icons in the repo README

[joshtrichards]

The status icons at the top of the README have been reporting weird states for awhile. These drive me crazy every time I see them, but I don't have the time to figure out what is going on with them at the moment (they're not accurate or pulling from the right place or something):

[![GitHub CI build status badge](https://github.com/nextcloud/docker/workflows/Images/badge.svg)](https://github.com/nextcloud/docker/actions?query=workflow%3AImages)
[![update.sh build status badge](https://github.com/nextcloud/docker/workflows/update.sh/badge.svg)](https://github.com/nextcloud/docker/actions?query=workflow%3Aupdate.sh)
[![amd64 build status badge](https://img.shields.io/jenkins/s/https/doi-janky.infosiftr.net/job/multiarch/job/amd64/job/nextcloud.svg?label=amd64)](https://doi-janky.infosiftr.net/job/multiarch/job/amd64/job/nextcloud)
[![arm32v5 build status badge](https://img.shields.io/jenkins/s/https/doi-janky.infosiftr.net/job/multiarch/job/arm32v5/job/nextcloud.svg?label=arm32v5)](https://doi-janky.infosiftr.net/job/multiarch/job/arm32v5/job/nextcloud)
[![arm32v6 build status badge](https://img.shields.io/jenkins/s/https/doi-janky.infosiftr.net/job/multiarch/job/arm32v6/job/nextcloud.svg?label=arm32v6)](https://doi-janky.infosiftr.net/job/multiarch/job/arm32v6/job/nextcloud)
[![arm32v7 build status badge](https://img.shields.io/jenkins/s/https/doi-janky.infosiftr.net/job/multiarch/job/arm32v7/job/nextcloud.svg?label=arm32v7)](https://doi-janky.infosiftr.net/job/multiarch/job/arm32v7/job/nextcloud)
[![arm64v8 build status badge](https://img.shields.io/jenkins/s/https/doi-janky.infosiftr.net/job/multiarch/job/arm64v8/job/nextcloud.svg?label=arm64v8)](https://doi-janky.infosiftr.net/job/multiarch/job/arm64v8/job/nextcloud)
[![i386 build status badge](https://img.shields.io/jenkins/s/https/doi-janky.infosiftr.net/job/multiarch/job/i386/job/nextcloud.svg?label=i386)](https://doi-janky.infosiftr.net/job/multiarch/job/i386/job/nextcloud)
[![mips64le build status badge](https://img.shields.io/jenkins/s/https/doi-janky.infosiftr.net/job/multiarch/job/mips64le/job/nextcloud.svg?label=mips64le)](https://doi-janky.infosiftr.net/job/multiarch/job/mips64le/job/nextcloud)
[![ppc64le build status badge](https://img.shields.io/jenkins/s/https/doi-janky.infosiftr.net/job/multiarch/job/ppc64le/job/nextcloud.svg?label=ppc64le)](https://doi-janky.infosiftr.net/job/multiarch/job/ppc64le/job/nextcloud)
[![s390x build status badge](https://img.shields.io/jenkins/s/https/doi-janky.infosiftr.net/job/multiarch/job/s390x/job/nextcloud.svg?label=s390x)](https://doi-janky.infosiftr.net/job/multiarch/job/s390x/job/nextcloud)