Revert "playbook: use OBS Debian 9 for all version of Debian <= 9"

This reverts commit 097e1cd0.

This is not working because of dependencies on newer libc6 and
libstdc++6.

playbook/roles/repository/tasks/main.yml

@@ -26,7 +26,11 @@
 
   - name: Install Debian 9 repository key
     apt_key: url={{ base_open_build_url }}/Debian_9.0/Release.key state=present
-    when: ansible_distribution == "Debian" and ansible_distribution_major_version <= "9"
+    when: ansible_distribution == "Debian" and ansible_distribution_major_version == "9"
+
+  - name: Install Debian 8 repository key
+    apt_key: url={{ base_open_build_url }}/Debian_8.0/Release.key state=present
+    when: ansible_distribution == "Debian" and ansible_distribution_major_version == "8"
 
   - name: Install Debian 11 repository
     apt_repository: repo='deb {{ base_open_build_url }}/Debian_11/ ./' state=present
@@ -38,7 +42,11 @@
 
   - name: Install Debian 9 repository
     apt_repository: repo='deb {{ base_open_build_url }}/Debian_9.0/ ./' state=present
-    when: ansible_distribution == "Debian" and ansible_distribution_major_version <= "9"
+    when: ansible_distribution == "Debian" and ansible_distribution_major_version == "9"
+
+  - name: Install Debian 8 repository
+    apt_repository: repo='deb {{ base_open_build_url }}/Debian_8.0/ ./' state=present
+    when: ansible_distribution == "Debian" and ansible_distribution_major_version == "8"
 
   - name: Install Ubuntu 14.04 repository key
     apt_key: url={{ base_open_build_url }}/xUbuntu_14.04/Release.key state=present

playbook/sha256sum

-73bdefddd86c1bb8d585c0f0d1d636a9bf3bca1a787c3de9ab2cd08591e21c31  -
+e4b015775c67f46178e3e569eacbc97319395fe47fe0070b610f5ca0411f70b7  -