refactor(cloudbees-amd64-jenkins-jobs): remove unnecessary entrypoint

Change-Id: I6cd079e17d2f850293d429bf0d25e509cac342ef
Signed-off-by: Chris Kay <chris.kay@arm.com>
diff --git a/cloudbees-amd64-jenkins-jobs/Dockerfile b/cloudbees-amd64-jenkins-jobs/Dockerfile
index 753ccee..d6196ff 100644
--- a/cloudbees-amd64-jenkins-jobs/Dockerfile
+++ b/cloudbees-amd64-jenkins-jobs/Dockerfile
@@ -11,5 +11,3 @@
     uv venv "/home/jenkins/.venv" --python "$(cat "/tmp/.python-version")" --python-preference only-managed
     uv pip install --requirements "/tmp/requirements.txt"
 EOF
-
-ENTRYPOINT ["/bin/cat"]