Merge branch 'fix-migration-paths' into 'master'

Fix migration paths

This fixes `migration paths` failure, preventing the `knapsack` from auto-balancing test suites:
https://gitlab.com/gitlab-org/gitlab-ce/builds/6485942

cc @stanhu

See merge request !7640

.gitlab-ci.yml

@@ -319,12 +319,11 @@ migration paths:
     - master@gitlab/gitlabhq
     - master@gitlab/gitlab-ee
   script:
-    - git checkout HEAD .
-    - git fetch --tags
-    - git checkout v8.5.9
+    - git fetch origin v8.5.9
+    - git checkout -f FETCH_HEAD
     - cp config/resque.yml.example config/resque.yml
     - sed -i 's/localhost/redis/g' config/resque.yml
-    - bundle install --without postgres production --jobs $(nproc) "${FLAGS[@]}" --retry=3
+    - bundle install --without postgres production --jobs $(nproc) ${FLAGS[@]} --retry=3
     - rake db:drop db:create db:schema:load db:seed_fu
     - git checkout $CI_BUILD_REF
     - source scripts/prepare_build.sh