remove old merge code from circle template

.circleci/config.yml

@@ -17,22 +17,6 @@ common: &common
         name: merge pull request base (3nd try)
         command: ./.circleci/merge_pr.sh
         when: on_fail
-    - run:
-        name: merge pull request base
-        command: |
-          if [[ -n "${CIRCLE_PR_NUMBER}" ]]; then
-            PR_INFO_URL=https://api.github.com/repos/$CIRCLE_PROJECT_USERNAME/$CIRCLE_PROJECT_REPONAME/pulls/$CIRCLE_PR_NUMBER
-
-            PR_BASE_BRANCH=$(curl -L "$PR_INFO_URL" | python -c 'import json, sys; obj = json.load(sys.stdin); sys.stdout.write(obj["base"]["ref"])')
-            git fetch origin +"$PR_BASE_BRANCH":circleci/pr-base
-
-            # We need these config values or git complains when creating the
-            # merge commit
-            git config --global user.name "Circle CI"
-            git config --global user.email "circleci@example.com"
-
-            git merge --no-edit circleci/pr-base
-          fi
     - restore_cache:
         keys:
           - cache-{{ .Environment.CIRCLE_JOB }}-{{ checksum "setup.py" }}-{{ checksum "tox.ini" }}