Use new build-image with tanka in all CI pipelines

Signed-off-by: Jack Baldry <[email protected]>

Author: jdbaldry

.circleci/config.yml

@@ -11,22 +11,22 @@ workflows:
 jobs:
   lint:
     docker:
-      - image: grafana/cortex-jsonnet-build-image:387f7ca
+      - image: grafana/cortex-jsonnet-build-image:55f5699
     steps:
       - checkout
       - run: make lint
 
   build:
     docker:
-      - image: grafana/cortex-jsonnet-build-image:387f7ca
+      - image: grafana/cortex-jsonnet-build-image:55f5699
     steps:
       - checkout
       - run: make build-mixin
       - store_artifacts:
           path: cortex-mixin.zip
   test-readme:
     docker:
-      - image: grafana/cortex-jsonnet-build-image:387f7ca
+      - image: grafana/cortex-jsonnet-build-image:55f5699
     steps:
       - checkout
       - run: make test-readme