Fix devcontainer Dockerfile - add Yarn GPG key and repository

[martclau]

Building on Ubuntu 24.04.4 using Docker 29.3.0 hits a missing requirement. The change fixes this by adding the Yarn repo and PGP key.

$ sudo docker build --no-cache -f .devcontainer/Dockerfile -t raptor-devcontainer:latest .
[+] Building 2.4s (6/17) docker:default
=> [internal] load build definition from Dockerfile 0.0s
=> => transferring dockerfile: 5.86kB 0.0s
=> [internal] load metadata for mcr.microsoft.com/devcontainers/python:1-3.12-bookworm 0.1s
=> [internal] load .dockerignore 0.0s
=> => transferring context: 2B 0.0s
=> CACHED [ 1/13] FROM mcr.microsoft.com/devcontainers/python:1-3.12-bookworm@sha256:7876580dc67fd460fd962f004cbeb480027e9bbc0657096f1087db11f9eaff39 0.0s
=> => resolve mcr.microsoft.com/devcontainers/python:1-3.12-bookworm@sha256:7876580dc67fd460fd962f004cbeb480027e9bbc0657096f1087db11f9eaff39 0.0s
=> [internal] load build context 0.0s
=> => transferring context: 187B 0.0s
=> ERROR [ 2/13] RUN apt-get update && export DEBIAN_FRONTEND=noninteractive && apt-get install -y --no-install-recommends python3-pip python3-venv git build-essential gcc g++ make cmake autoconf 2.0s

[ 2/13] RUN apt-get update && export DEBIAN_FRONTEND=noninteractive && apt-get install -y --no-install-recommends python3-pip python3-venv git build-essential gcc g++ make cmake autoconf automake libtool libtool-bin clang-format gdb gdb-multiarch binutils file curl wget libcapnp-dev fonts-liberation libatk1.0-0 libatk-bridge2.0-0 libc6 libcairo2 libcap2 libcups2 libdbus-1-3 libexpat1 libfontconfig1 libgcc1 libgconf-2-4 libgdk-pixbuf2.0-0 libglib2.0-0 libgtk-3-0 libnspr4 libnss3 libpango-1.0-0 libpangocairo-1.0-0 libx11-6 libx11-xcb1 libxcb1 libxcomposite1 libxcursor1 libxdamage1 libxext6 libxfixes3 libxi6 libxrandr2 libxrender1 libxss1 libxtst6 lsb-release ca-certificates jq unzip && apt-get clean && rm -rf /var/lib/apt/lists/*:
0.328 Get:1 http://deb.debian.org/debian bookworm InRelease [151 kB]
0.356 Get:2 http://deb.debian.org/debian bookworm-updates InRelease [55.4 kB]
0.362 Get:3 http://deb.debian.org/debian-security bookworm-security InRelease [48.0 kB]
0.367 Get:4 https://dl.yarnpkg.com/debian stable InRelease
0.449 Get:5 http://deb.debian.org/debian bookworm/main amd64 Packages [8792 kB]
0.640 Err:4 https://dl.yarnpkg.com/debian stable InRelease
0.640 The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 62D54FD4003F6525
0.724 Get:6 http://deb.debian.org/debian bookworm-updates/main amd64 Packages [6924 B]
0.735 Get:7 http://deb.debian.org/debian-security bookworm-security/main amd64 Packages [293 kB]
1.500 Reading package lists...
1.973 W: GPG error: https://dl.yarnpkg.com/debian stable InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 62D54FD4003F6525
1.973 E: The repository 'https://dl.yarnpkg.com/debian stable InRelease' is not signed.

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