Disable juint reports tmp

The junit reports are creating 90mb files inside of redis for
`gitlab-ce/ee` project. There is an ongoing production incident
https://gitlab.com/gitlab-com/gl-infra/production/issues/928 that is
because of high CPU uitlaization on the redis nodes. GitLab-ce/ee are
the highest consumers of memory becuase of these junit reports.

This is a bandage until we can scale redis properly.

.gitlab/ci/frontend.gitlab-ci.yml

@@ -168,8 +168,8 @@ karma:
     paths:
       - chrome_debug.log
       - coverage-javascript/
-    reports:
-      junit: junit_karma.xml
+#    reports:
+#      junit: junit_karma.xml
 jest:
   extends: .dedicated-no-docs-and-no-qa-pull-cache-job
@@ -191,8 +191,8 @@ jest:
     paths:
       - coverage-frontend/
       - junit_jest.xml
-    reports:
-      junit: junit_jest.xml
+#    reports:
+#      junit: junit_jest.xml
   cache:
     key: jest
     paths:

.gitlab/ci/rails.gitlab-ci.yml

@@ -77,8 +77,8 @@
       - rspec_flaky/
       - rspec_profiling/
       - tmp/capybara/
-    reports:
-      junit: junit_rspec.xml
+#    reports:
+#      junit: junit_rspec.xml
 .rspec-metadata-pg: &rspec-metadata-pg
   <<: *rspec-metadata