Re-pin Docker image ubuntu:rolling

ubuntu:rolling@sha256:26c68657ccce2cb0a31b330cb0be2b5e108d467f641c62e13ab40cbec258c68d
->
ubuntu:rolling@sha256:18f63cbe22f65810c15453f050cb64603193264b039661389efb2cd20f2b236a

 [atomist:generated]
 [atomist-skill:atomist/docker-base-image-policy]

Signed-off-by: Atomist Bot <[email protected]>

Author: atomist-bot

Dockerfile

@@ -9,7 +9,7 @@ RUN npm ci --no-optional && \
     npm run compile && \
     rm -rf node_modules .git
 
-FROM ubuntu:rolling@sha256:26c68657ccce2cb0a31b330cb0be2b5e108d467f641c62e13ab40cbec258c68d
+FROM ubuntu:rolling@sha256:18f63cbe22f65810c15453f050cb64603193264b039661389efb2cd20f2b236a
 
 # tools
 RUN apt-get update && apt-get install -y \