Add `resistor-color-duo` exercise #15

	# This workflow will do a clean install of the dependencies and run the linter
	#
	# Requires scripts:
	# - bin/run_lints.R

	name: Lint exercises

	on:
	push:
	branches: [main]
	pull_request:
	branches: [main]
	workflow_dispatch:

	jobs:
	lint:
	runs-on: ubuntu-22.04

	steps:
	- uses: actions/checkout@d632683dd7b4114ad314bca15554477dd762a938

	- uses: r-lib/actions/setup-r@v2
	with:
	r-version: 4.3.1
	use-public-rspm: true

	- name: Install project dependencies
	run: \|
	install.packages(c("testthat", "jsonlite", "lintr"))
	shell: Rscript {0}

	- name: Run exercism/r ci pre-check (checks config, lint code) for all exercises
	run: \|
	source("bin/run_lints.R")
	shell: Rscript {0}

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