Update dependency score_bazel_cpp_toolchains to v1.0.3 - #288

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: bazel-contrib/setup-bazel@77a1d3d18379c7cb0a7e3b9fcaaa4d94f1029763. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/