feat(dependabot): add dependabot configuration for bundler, npm, and docker updates

refactor(dockerfile): parameterize Ruby, Node, and Bundler versions for flexibility
chore: remove renovate configuration in favor of dependabot

Author: ale-saglia

.devcontainer/Dockerfile

@@ -1,4 +1,11 @@
-FROM ruby:3.3-bookworm
+ARG RUBY_VERSION=3.3
+ARG NODE_VERSION=20
+ARG BUNDLER_VERSION=2.3.25
+
+FROM ruby:${RUBY_VERSION}-bookworm
+
+ARG NODE_VERSION
+ARG BUNDLER_VERSION
 
 RUN apt-get update && apt-get install -y --no-install-recommends \
     curl \
@@ -9,11 +16,11 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
     sudo \
     && rm -rf /var/lib/apt/lists/*
 
-RUN curl -fsSL https://deb.nodesource.com/setup_20.x | bash - \
+RUN curl -fsSL https://deb.nodesource.com/setup_${NODE_VERSION}.x | bash - \
     && apt-get install -y --no-install-recommends nodejs \
     && rm -rf /var/lib/apt/lists/*
 
-RUN gem install bundler:2.3.25
+RUN gem install bundler:${BUNDLER_VERSION}
 
 ARG USERNAME=vscode
 ARG USER_UID=1000

.github/dependabot.yml

@@ -0,0 +1,24 @@
+version: 2
+updates:
+  - package-ecosystem: "bundler"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+      day: "monday"
+    groups:
+      ruby-deps:
+        patterns: ["*"]
+
+  - package-ecosystem: "npm"
+    directory: "/scripts/og-image-gen"
+    schedule:
+      interval: "weekly"
+      day: "monday"
+    groups:
+      js-deps:
+        patterns: ["*"]
+
+  - package-ecosystem: "docker"
+    directory: "/.devcontainer"
+    schedule:
+      interval: "monthly"