[fix]修正XmlConfig保存配置文件错误，错误判空导致未能正确写入配置类中的空属性。尽管XmlConfig已经过期多年，但一些老项… #256

	name: publish-beta

	on:
	push:
	branches: [ master, dev ]
	paths:
	- 'NewLife.Core/**'
	pull_request:
	branches: [ master, dev ]
	paths:
	- 'NewLife.Core/**'
	workflow_dispatch:

	jobs:
	build-publish:
	runs-on: windows-latest

	steps:
	- uses: actions/checkout@v4
	- name: Setup dotNET
	uses: actions/setup-dotnet@v3
	with:
	dotnet-version: \|
	6.0.x
	7.0.x
	8.x
	- name: Get Version
	run: echo "VERSION=$(date '+%Y.%m%d-beta%H%M')" \| Out-File -FilePath $env:GITHUB_ENV -Encoding utf8 -Append
	- name: Build
	run: \|
	dotnet build -c Release --version-suffix ${{ env.VERSION }}
	- name: Pack
	run: \|
	dotnet pack --no-build --version-suffix ${{ env.VERSION }} -c Release -o out NewLife.Core\NewLife.Core.csproj

	- name: Publish
	run: \|
	dotnet nuget push .\out\*.nupkg --skip-duplicate --source https://nuget.pkg.github.com/NewLifeX/index.json --api-key ${{ github.token }}
	dotnet nuget push .\out\*.nupkg --skip-duplicate --source https://api.nuget.org/v3/index.json --api-key ${{ secrets.nugetKey }}

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