fix(config): move endpoint, platform to GlobalConfig (#15864)

lib/config/global.ts

lib/config/presets/index.spec.ts

lib/config/presets/index.ts

lib/config/presets/local/index.spec.ts

lib/config/presets/local/index.ts

lib/config/presets/types.ts

lib/config/types.ts

lib/modules/manager/gitlabci-include/extract.spec.ts

lib/modules/manager/gitlabci-include/extract.ts

lib/modules/manager/npm/post-update/index.ts

lib/modules/manager/types.ts

lib/util/cache/repository/index.spec.ts

lib/util/cache/repository/init.ts

lib/workers/global/index.ts

lib/workers/repository/init/index.ts

lib/workers/repository/onboarding/branch/config.spec.ts

lib/workers/repository/onboarding/branch/config.ts

lib/workers/types.ts