Use inline variable to simplify ext::nullopt declaration #2731

	name: Check test times
	on: [push, pull_request]
	jobs:
	check-test-times:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- name: Cache
	uses: hendrikmuhs/[email protected]
	with:
	key: linux-ci-test-times-${{ github.ref }}
	restore-keys: \|
	linux-ci-test-times-${{ github.ref }}
	linux-ci-test-times-refs/heads/master
	linux-ci-test-times-
	- name: Setup
	run: \|
	sudo rm /etc/apt/sources.list.d/microsoft-prod.list
	sudo apt update
	sudo apt install -y libboost-dev autoconf automake libtool ccache
	- name: Build
	run: \|
	./autogen.sh
	./configure --disable-static CC="ccache gcc" CXX="ccache g++" CXXFLAGS="-O2 -g0"
	make -j 4
	- name: Run faster tests
	run: \|
	./test-suite/quantlib-test-suite --logger=JUNIT,warning,faster.xml:HRF,message -- --faster
	- name: Run fast tests
	run: \|
	./test-suite/quantlib-test-suite --logger=JUNIT,warning,fast.xml:HRF,message -- --fast
	- name: Run all tests
	run: \|
	./test-suite/quantlib-test-suite --logger=JUNIT,warning,all.xml:HRF,message
	- name: Save test times
	uses: actions/upload-artifact@v4
	with:
	name: test-reports
	path: ./*.xml
	- name: Check test times
	run: \|
	python ./tools/check_test_times.py

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