bump node image for CI

Signed-off-by: Grant Linville <grant@acorn.io>

Author: g-linville

Makefile

@@ -49,11 +49,11 @@ serve-docs:
 
 # This will initialize the node_modules needed to run the docs dev server. Run this before running serve-docs
 init-docs:
-	docker run --rm --workdir=/docs -v $${PWD}/docs:/docs node:18-buster yarn install
+	docker run --rm --workdir=/docs -v $${PWD}/docs:/docs node:20-bullseye yarn install
 
 # Ensure docs build without errors. Makes sure generated docs are in-sync with CLI.
 validate-docs: gen-docs
-	docker run --rm --workdir=/docs -v $${PWD}/docs:/docs node:18-buster yarn build
+	docker run --rm --workdir=/docs -v $${PWD}/docs:/docs node:20-bullseye yarn build
 	if [ -n "$$(git status --porcelain --untracked-files=no)" ]; then \
 		git status --porcelain --untracked-files=no; \
 		echo "Encountered dirty repo!"; \