Fix nil pointer dereference within `refresh` error path #279

	name: Build & Test

	on:
	pull_request:
	branches:
	- main
	paths:
	- '**.go'
	- 'go.mod'
	- 'go.sum'
	- '.github/workflows/build-and-test.yaml'

	jobs:
	build:
	runs-on: ubuntu-latest
	steps:
	- name: Checkout
	uses: actions/checkout@v4
	with:
	fetch-depth: 0

	- name: Set up Go
	uses: actions/setup-go@v5
	with:
	go-version-file: go.mod

	- name: Cache Go modules
	uses: actions/cache@v4
	with:
	path: ~/go/pkg/mod
	key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
	restore-keys: \|
	${{ runner.os }}-go-

	- name: Go vet
	run: \|
	go vet ./...
	go vet github.com/theurichde/go-aws-sso/internal

	- name: Tests
	run: \|
	go clean -r -testcache
	go clean -r -x -modcache
	go clean -r -x -testcache
	go clean -r -x -cache
	go test -v ./...
	go test -v github.com/theurichde/go-aws-sso/internal

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