Add helper for making RSA key from exponent and modulus #224

	name: Specific Targets CI

	on:
	push:
	branches: [master]
	pull_request:
	branches: [master]
	paths:
	- "CMakeLists.txt"
	- "cmake/**"
	- "include/jwt-cpp/**"
	- "tests/cmake/**"
	- ".github/actions/**"
	- ".github/workflows/targets.yml"

	jobs:
	gcc-4-8:
	name: GCC 4.8
	runs-on: ubuntu-latest
	container:
	image: ubuntu:bionic-20230530 # 18.04
	env:
	CC: /usr/bin/gcc-4.8
	CXX: /usr/bin/g++-4.8
	steps:
	- run: \|
	apt-get update
	apt-get install -y g++-4.8 wget make libssl-dev
	- uses: actions/checkout@v3
	- uses: ./.github/actions/install/cmake
	with:
	version: "3.26.3"
	url: "https://cmake.org/files/v3.26/cmake-3.26.3.tar.gz"

	- name: setup
	run: \|
	mkdir build
	cd build
	cmake ..
	cmake --install .
	- name: test
	working-directory: tests/cmake
	run: \|
	CC=gcc-4.8 CXX=g++-4.8 cmake . -DTEST:STRING="defaults-enabled"
	cmake --build .

	gcc-12:
	runs-on: ubuntu-latest
	container:
	image: ubuntu:jammy-20231004 # 22.04
	env:
	CC: /usr/bin/gcc-12
	CXX: /usr/bin/g++-12
	steps:
	- run: \|
	apt-get update
	apt-get install -y g++-12 wget make libssl-dev
	- uses: actions/checkout@v3
	- uses: ./.github/actions/install/cmake
	with:
	version: "3.26.3"
	url: "https://cmake.org/files/v3.26/cmake-3.26.3.tar.gz"

	- name: setup
	run: \|
	mkdir build
	cd build
	cmake ..
	cmake --install .

	- name: test
	working-directory: tests/cmake
	run: \|
	CC=gcc-12 CXX=g++-12 cmake . -DCMAKE_CXX_STANDARD=20 -DTEST:STRING="defaults-enabled"
	cmake --build .

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