Better support for additional package.json attributes

[adierkens]

Release Notes

Adds new rules to the package.json creation pipeline:

Adds merge_json rule to flatten multiple json files into one. This can be combined with the base_package_json attribute to create more dynamic package attributes.

Adds a create_contributors rule for generating the contributors section of a package.json from an .all-contributorsrc

Example:

load("@rules_player//javascript/package_json:index.bzl", "merge_json", "create_contributors")

create_contributors(
    name = "pkg_json_contrib",
    all_contributors = "//:.all-contributorsrc",
)

merge_json(
    name = "pkg_json_template",
    srcs = [
        "package-template.json",
        ":pkg_json_contrib",
    ]
)

[intuit-svc]

🚀 PR was released in v0.5.0 🚀