VOL-5176: Purge 2.8 jobs

This also includes moving several jobs back to their original build
agent, since build agent issues have been fixed.

Signed-off-by: Eric Ball <eball@linuxfoundation.org>
Change-Id: I2adfc8a65dfa7cacb80a59fc418cb3b00a7e5ffe
diff --git a/jjb/verify/voltha-system-tests.yaml b/jjb/verify/voltha-system-tests.yaml
index 44f7449..bb7e979 100644
--- a/jjb/verify/voltha-system-tests.yaml
+++ b/jjb/verify/voltha-system-tests.yaml
@@ -7,30 +7,21 @@
 
     jobs:
       - 'verify-voltha-system-tests-jobs':
-          # build-node: 'ubuntu18.04-basebuild-4c-8g'
-          build-node: 'ubuntu18.04-basebuild-8c-15g'
+          build-node: 'ubuntu18.04-basebuild-4c-8g'
           branch-regexp: '{all-branches-regexp}'
       - 'verify-voltha-system-tests-jobs-master':
-          # build-node: 'ubuntu18.04-basebuild-4c-8g'
-          build-node: 'ubuntu18.04-basebuild-8c-15g'
+          build-node: 'ubuntu18.04-basebuild-4c-8g'
           branch-regexp: '^master$'
       - 'verify-voltha-system-tests-jobs-voltha-2.12':
-          # build-node: 'ubuntu18.04-basebuild-4c-8g'
-          build-node: 'ubuntu18.04-basebuild-8c-15g'
+          build-node: 'ubuntu18.04-basebuild-4c-8g'
           name-extension: '-voltha-2.12'
           override-branch: 'voltha-2.12'
           branch-regexp: '^voltha-2.12$'
       - 'verify-voltha-system-tests-jobs-voltha-2.11':
-          # build-node: 'ubuntu18.04-basebuild-4c-8g'
-          build-node: 'ubuntu18.04-basebuild-8c-15g'
+          build-node: 'ubuntu18.04-basebuild-4c-8g'
           name-extension: '-voltha-2.11'
           override-branch: 'voltha-2.11'
           branch-regexp: '^voltha-2.11$'
-#      - 'verify-voltha-system-tests-jobs-voltha-2.8':
-#          build-node: 'ubuntu18.04-basebuild-4c-8g'
-#          name-extension: '-voltha-2.8'
-#          override-branch: 'voltha-2.8'
-#          branch-regexp: '^voltha-2.8$'
 
 - job-group:
     name: 'verify-voltha-system-tests-jobs'
@@ -55,12 +46,6 @@
           pipeline-script: 'voltha/voltha-2.11/bbsim-tests.groovy'
           pipeline-branch: 'voltha-2.11'
 
-#- job-group:
-#    name: 'verify-voltha-system-tests-jobs-voltha-2.8'
-#    jobs:
-#      - 'voltha-patch-test':
-#          pipeline-script: 'voltha/voltha-2.8/bbsim-tests.groovy'
-
 - job-group:
     name: 'verify-voltha-system-tests-jobs-master'
     jobs: