Revert null values to return <nil> instead of empty. Closes #77 #9

	name: Acceptance Tests
	on:
	pull_request:

	jobs:
	build_test:
	name: Build test
	runs-on: ubuntu-latest
	steps:
	- name: Set up Go
	uses: actions/setup-go@v5
	with:
	go-version: 1.21

	- name: Checkout
	uses: actions/checkout@v4

	- name: Fetching Go Cache Paths
	id: go-cache-paths
	run: \|
	echo "go-build=$(go env GOCACHE)" >> $GITHUB_OUTPUT
	echo "go-mod=$(go env GOMODCACHE)" >> $GITHUB_OUTPUT

	- name: Go Build Cache
	id: build-cache
	uses: actions/cache@v4
	with:
	path: ${{ steps.go-cache-paths.outputs.go-build }}
	key: ${{ runner.os }}-go-build-${{ hashFiles('**/go.sum') }}

	- name: Go Mod Cache
	id: mod-cache
	uses: actions/cache@v4
	with:
	path: ${{ steps.go-cache-paths.outputs.go-mod }}
	key: ${{ runner.os }}-go-mod-${{ hashFiles('**/go.sum') }}

	- name: Test building export tool with chaos plugin
	run: \|
	make build plugin=chaos

	- name: Check binary is created
	run: \|
	/usr/local/bin/steampipe_export_chaos --version

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