chore(package): pin ghcr.io/marinatedconcrete/devcontainer-base docker tag to a0b5ff1 (#793)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| ghcr.io/marinatedconcrete/devcontainer-base | final | pinDigest | →
`a0b5ff1` |

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images/github-runner-ci/Containerfile

@@ -2,7 +2,7 @@ FROM scratch AS ctx
 COPY build_files /
 
 # hadolint ignore=DL3007
-FROM ghcr.io/marinatedconcrete/devcontainer-base:latest
+FROM ghcr.io/marinatedconcrete/devcontainer-base:latest@sha256:a0b5ff1fb1717131f17ef8abeabd02e00727873b8ba64ecae7824c9f05d4cbfd
 
 LABEL org.opencontainers.image.title="github-runner-ci"
 LABEL org.opencontainers.image.description="A CI job image for ARC kubernetes-novolume runners."