fix divu when theta=0 or pi #1275

	name: reacting-convergence-true-sdc

	on: [pull_request]
	jobs:
	reacting-convergence-true-sdc:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	with:
	fetch-depth: 0

	- name: Get submodules
	run: \|
	git submodule update --init
	cd external/Microphysics
	git fetch; git checkout development
	cd ../amrex
	git fetch; git checkout development
	cd ../..

	- name: Install dependencies
	run: \|
	sudo apt-get update -y -qq
	sudo apt-get -qq -y install curl g++>=9.3.0

	- name: Compile reacting_convergence
	run: \|
	cd Exec/reacting_tests/reacting_convergence
	make DIM=2 USE_MPI=FALSE -j 4 USE_TRUE_SDC=TRUE

	- name: Run reacting_convergence
	run: \|
	cd Exec/reacting_tests/reacting_convergence
	./Castro2d.gnu.TRUESDC.ex inputs.128.testsuite max_step=10

	- name: Build the fextrema tool
	run: \|
	cd external/amrex/Tools/Plotfile
	make programs=fextrema -j 4

	- name: Check the extrema
	run: \|
	cd Exec/reacting_tests/reacting_convergence
	../../../external/amrex/Tools/Plotfile/fextrema.gnu.ex react_converge_128_plt00010 > fextrema.out
	# ignore angular momenta, since 0 and -0 don't compare
	diff -I "^ angular_momentum" fextrema.out ci-benchmarks/react_converge_128_true_sdc.out

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