bump golang to 1.23, golangci-lint to v2, fix errors #30

	name: RTF CI
	on: [push, pull_request]

	jobs:
	test:
	name: Test

	runs-on: ubuntu-latest
	steps:

	- name: Set up Go 1.23
	uses: actions/setup-go@v5
	with:
	go-version: 1.23.4
	id: go

	- name: Set path
	run: echo "$(go env GOPATH)/bin" >> $GITHUB_PATH
	env:
	GOPATH: ${{runner.workspace}}

	- name: Check out code
	uses: actions/checkout@v3

	- name: Get pre-requisites
	run: \|
	make install-deps
	env:
	GOPATH: ${{runner.workspace}}

	- name: Tests
	run: \|
	make test
	env:
	GOPATH: ${{runner.workspace}}

	build:
	name: Build
	needs: test
	strategy:
	matrix:
	os: [linux,darwin,windows]

	runs-on: ubuntu-latest
	steps:

	- name: Set up Go 1.23
	uses: actions/setup-go@v5
	with:
	go-version: 1.23.4
	id: go

	- name: Check out code
	uses: actions/checkout@v4

	- name: build
	id: build
	run: \|
	if grep -q "windows" <<< "${{matrix.os}}"; then
	export TARGET="windows.exe"
	else
	export TARGET="${{matrix.os}}"
	fi
	echo "::set-output name=binary::rtf-$TARGET"
	make clean
	GOOS=${{matrix.os}} make
	mv rtf "rtf-${TARGET}"
	env:
	GOPATH: ${{runner.workspace}}

	- name: Upload binary
	uses: actions/upload-artifact@v3
	with:
	name: rtf-binaries
	path: ${{steps.build.outputs.binary}}

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