dxf: fix dxf_fixup_string logic #759

	name: ODA
	on:
	push:
	branches:
	- master
	- smoke/*
	- work/oda

	# cancel older workflow runs
	concurrency:
	group: ${{ github.workflow }}-${{ github.event.pull_request.number \|\| github.ref }}
	cancel-in-progress: true

	jobs:
	oda:
	#ubuntu-22.04
	runs-on: self-hosted
	timeout-minutes: 50
	strategy:
	fail-fast: true
	steps:
	- uses: actions/checkout@v4
	with:
	fetch-depth: 1
	submodules: recursive
	- name: setup-python
	uses: actions/setup-python@v5
	with:
	python-version: '3.10'
	- uses: pyvista/setup-headless-display-action@v1
	#- run: \|
	# deb=ODAFileConverter_QT6_lnxX64_8.3dll_25.7.deb
	# wget https://download.opendesign.com/guestfiles/Demo/$deb
	# sudo add-apt-repository -y ppa:linuxuprising/libpng12
	# sudo apt update
	# sudo apt-get -y install libpng12-0 qt5dxcb-plugin
	# sudo dpkg -i $deb
	# cd /usr/lib/x86_64-linux-gnu
	# sudo ln -s libxcb-util.so.1 libxcb-util.so.0
	- run: \|
	export QT_DEBUG_PLUGINS=1
	ODAFileConverter test/test-data . ACAD2000 DXF 0 0 example_2000.dwg \|\| true
	test -f example_2000.dxf \|\| (cat example_2000.dxf.err; exit 1)
	echo ODAFileConverter works ok
	export QT_DEBUG_PLUGINS=
	- uses: hendrikmuhs/[email protected]
	with:
	create-symlink: true
	key: ${{ github.job }}
	- run: sh autogen.sh
	- run: CFLAGS=-O0 ./configure --disable-bindings
	- run: make -j
	- run: make -j check -C programs TESTS=json.test
	# this makes it green, but we want it red
	#continue-on-error: true

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