docker: Upgrade os-autoinst_dev image to Tumbleweed

Tested locally with

```
podman build -t os-autoinst_dev -f container/os-autoinst_dev/Dockerfile container/os-autoinst_dev/
podman run --rm -it --entrypoint='' os-autoinst_dev /bin/bash -c 'cd /opt && git clone https://github.com/os-autoinst/os-autoinst && cd os-autoinst && mkdir build && cd build && cmake -GNinja .. && ninja'
```

Related progress issue: https://progress.opensuse.org/issues/80962

container/os-autoinst_dev/Dockerfile

@@ -1,12 +1,12 @@
 #!BuildTag: os-autoinst_dev
 # hadolint ignore=DL3006
-FROM opensuse/leap:15.2
+FROM opensuse/tumbleweed
 
 # Define environment variable
 ENV NAME openQA test environment
 ENV LANG en_US.UTF-8
 
-RUN zypper ar -f -G 'http://download.opensuse.org/repositories/devel:/openQA:/Leap:/15.2/openSUSE_Leap_15.2' devel_openqa
+RUN zypper ar -f -G 'http://download.opensuse.org/repositories/devel:/openQA/openSUSE_Tumbleweed' devel_openqa
 
 # AUTODEPS START
 # This part is autogenerated by tools/update-deps from dependencies.yaml
@@ -129,7 +129,7 @@ RUN zypper in -y -C \
 # This QEMU binary requires the membarrier system call.
 # Please upgrade your system to a newer version of Linux
 
-#RUN zypper -n addrepo http://download.opensuse.org/repositories/devel:/openQA:/ci/openSUSE_Leap_15.2 qemu \
+#RUN zypper -n addrepo http://download.opensuse.org/repositories/devel:/openQA:/ci/openSUSE_Tumbleweed qemu \
 #    && zypper -n --gpg-auto-import-keys --no-gpg-checks refresh \
 #    && zypper -n in --from qemu qemu qemu-x86 qemu-tools qemu-ipxe qemu-sgabios qemu-seabios