remove envvar for s3 path from config file and error check s3 cp

.circleci/config.yml

@@ -21,7 +21,6 @@ references:
     GIT_AUTHOR_NAME: circleci-consul
     GIT_COMMITTER_NAME: circleci-consul
     S3_ARTIFACT_BUCKET:  consul-dev-artifacts
-    S3_ARTIFACT_PATH: consul-oss
 
 jobs:
   # build all distros
@@ -98,9 +97,14 @@ jobs:
       - run:
           name: Upload to s3
           command: |
+            if [ -n "${S3_ARTIFACT_PATH}" ]; then
               aws s3 cp \
               --metadata "CIRCLECI=${CIRCLECI},CIRCLE_BUILD_URL=${CIRCLE_BUILD_URL},CIRCLE_BRANCH=${CIRCLE_BRANCH}" \
               "consul.tar.gz" "s3://${S3_ARTIFACT_BUCKET}/${S3_ARTIFACT_PATH}/${CIRCLE_SHA1}.tar.gz"
+            else
+              echo "CircleCI - S3_ARTIFACT_PATH was not set"
+              exit 1
+            fi
 
   # Nomad 0.8 builds on go0.10
   # Run integration tests on nomad/v0.8.7