Bump nvidia/holodeck from v0.2.4 to v0.2.6 in /images/gh_runner

Bumps nvidia/holodeck from v0.2.4 to v0.2.6.

---
updated-dependencies:
- dependency-name: nvidia/holodeck
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

images/gh_runner/Dockerfile

@@ -1,5 +1,5 @@
 # Cache Holodeck image
-FROM ghcr.io/nvidia/holodeck:v0.2.4 AS holodeck
+FROM ghcr.io/nvidia/holodeck:v0.2.6 AS holodeck
 
 # https://github.com/actions/runner/blob/main/images/Dockerfile
 FROM ghcr.io/actions/actions-runner:2.319.1 AS runner