Avoid docker buildkite plugin, which is not supported by bkrun

ci/shellcheck.sh

@@ -5,10 +5,7 @@
 cd "$(dirname "$0")/.."
 
 set -x
-docker pull koalaman/shellcheck
-find -E . -name "*.sh" -not -regex ".*/(.cargo|node_modules)/.*" -print0 \
+find . -name "*.sh" -not -regex ".*/.cargo/.*" -not -regex ".*/node_modules/.*" -print0 \
   | xargs -0 \
-      docker run -w /work -v "$PWD:/work" \
-        koalaman/shellcheck --color=always --external-sources --shell=bash
-
+      ci/docker-run.sh koalaman/shellcheck --color=always --external-sources --shell=bash
 exit 0