Fix Base image build (#5254)

Title: Fix Cloud Build GPG errors and upgrade to Node.js 20 (LTS)

  Summary
This PR resolves the build failures in the clusterfuzz-images project
caused by missing or expired GPG keys in the legacy NodeSource
installation scripts. It also upgrades the base environment to use
Node.js 20 (LTS).

  Problem
  The existing docker/base build was failing with the following error:
GPG error: https://deb.nodesource.com/node_19.x focal InRelease: The
following signatures couldn't be verified because the public key is not
available: NO_PUBKEY 1655A0AB68576280

This was due to the use of the deprecated setup_19.x script and a
Node.js version (19) that is no longer supported.

  Solution
1. Upgraded to Node.js 20 (LTS): Migrated from Node 19 to the current
stable Long Term Support version.
2. Modernized Installation Method: Replaced the legacy 15,000-line
setup_19.x bash script with the modern, secure NodeSource installation
method using /etc/apt/keyrings and a signed repository entry.
3. Binary Version Consistency: Updated the Ubuntu 24.04 Dockerfile to
download and install the Node 20.12.2 (LTS) binary directly.
4. Cleanup: Removed the now-obsolete docker/base/setup_19.x script from
the repository.

  Changes
- docker/base/Dockerfile: Updated to use the new NodeSource apt
repository method for Node 20.
- docker/base/ubuntu-20-04.Dockerfile: Updated to use the new NodeSource
apt repository method for Node 20.
- docker/base/ubuntu-24-04.Dockerfile: Updated binary download URL and
extraction logic for Node 20.12.2.
   - docker/base/setup_19.x: Deleted.

  Impact
   - Fixes all base image builds in Cloud Build.
   - Ensures the project uses a supported, secure version of Node.js.
- Reduces technical debt by removing legacy scripts in favor of standard
Linux package management.

Author: javanlacerda

docker/base/Dockerfile

@@ -67,7 +67,8 @@ RUN apt-get update && \
         util-linux \
         wget \
         zip \
-        zlib1g-dev
+        zlib1g-dev \
+        gnupg
 
 COPY --from=xenial \
     /lib/x86_64-linux-gnu/libcrypto.so.1.0.0 \
@@ -127,8 +128,10 @@ RUN pip3.11 --no-cache-dir install pipenv==2022.8.5
 RUN ln -s /usr/local/bin/python3.11 /usr/bin/python3.11
 
 # Install Node.js
-COPY setup_19.x /data
-RUN bash setup_19.x && apt-get update -y && apt-get install -y nodejs
+RUN mkdir -p /etc/apt/keyrings && \
+    curl -fsSL https://deb.nodesource.com/gpgkey/nodesource-repo.gpg.key | gpg --dearmor -o /etc/apt/keyrings/nodesource.gpg && \
+    echo "deb [signed-by=/etc/apt/keyrings/nodesource.gpg] https://deb.nodesource.com/node_20.x nodistro main" | tee /etc/apt/sources.list.d/nodesource.list && \
+    apt-get update && apt-get install nodejs -y
 
 # Support i386.
 RUN dpkg --add-architecture i386