Update base node image to node:18-bookworm-slim

Signed-off-by: Nikolai Thingnes Leira <nikolai.thingnes.leira@soprasteria.com>

docs/deployment/docker.md

@@ -54,7 +54,7 @@ Once the host build is complete, we are ready to build our image. The following
 `Dockerfile` is included when creating a new app with `@backstage/create-app`:
 
 ```Dockerfile
-FROM node:18-bullseye-slim
+FROM node:18-bookworm-slim
 
 # Install isolate-vm dependencies, these are needed by the @backstage/plugin-scaffolder-backend.
 RUN --mount=type=cache,target=/var/cache/apt,sharing=locked \
@@ -160,7 +160,7 @@ the repo root:
 
 ```Dockerfile
 # Stage 1 - Create yarn install skeleton layer
-FROM node:18-bullseye-slim AS packages
+FROM node:18-bookworm-slim AS packages
 
 WORKDIR /app
 COPY package.json yarn.lock ./
@@ -173,7 +173,7 @@ COPY plugins plugins
 RUN find packages \! -name "package.json" -mindepth 2 -maxdepth 2 -exec rm -rf {} \+
 
 # Stage 2 - Install dependencies and build packages
-FROM node:18-bullseye-slim AS build
+FROM node:18-bookworm-slim AS build
 
 # Install isolate-vm dependencies, these are needed by the @backstage/plugin-scaffolder-backend.
 RUN --mount=type=cache,target=/var/cache/apt,sharing=locked \
@@ -211,7 +211,7 @@ RUN mkdir packages/backend/dist/skeleton packages/backend/dist/bundle \
     && tar xzf packages/backend/dist/bundle.tar.gz -C packages/backend/dist/bundle
 
 # Stage 3 - Build the actual backend image and install production dependencies
-FROM node:18-bullseye-slim
+FROM node:18-bookworm-slim
 
 # Install isolate-vm dependencies, these are needed by the @backstage/plugin-scaffolder-backend.
 RUN --mount=type=cache,target=/var/cache/apt,sharing=locked \

docs/local-dev/cli-build-system.md

@@ -418,7 +418,7 @@ The following is an example of a `Dockerfile` that can be used to package the
 output of building a package with role `'backend'` into an image:
 
 ```Dockerfile
-FROM node:18-bullseye-slim
+FROM node:18-bookworm-slim
 WORKDIR /app
 
 COPY yarn.lock package.json packages/backend/dist/skeleton.tar.gz ./

packages/backend/Dockerfile

@@ -9,7 +9,7 @@
 #
 # Once the commands have been run, you can build the image using `yarn build-image`
 
-FROM node:18-bullseye-slim
+FROM node:18-bookworm-slim
 
 # Install sqlite3 dependencies. You can skip this if you don't use sqlite3 in the image,
 # in which case you should also move better-sqlite3 to "devDependencies" in package.json.