Bump System.Text.Json from 6.0.6 to 7.0.3

Bumps [System.Text.Json](https://github.com/dotnet/runtime) from 6.0.6 to 7.0.3.
- [Release notes](https://github.com/dotnet/runtime/releases)
- [Commits](dotnet/runtime@v6.0.6...v7.0.3)

---
updated-dependencies:
- dependency-name: System.Text.Json
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

src/Simplify.Web.Postman/Simplify.Web.Postman.csproj

@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
 	<PropertyGroup>
 		<TargetFrameworks>net6.0;netstandard2.0</TargetFrameworks>
 		<LangVersion>10.0</LangVersion>
@@ -25,7 +25,7 @@
 	</PropertyGroup>
 	<ItemGroup>
 		<PackageReference Include="Simplify.Web" Version="4.6.0" />
-		<PackageReference Include="System.Text.Json" Version="6.0.6" />
+		<PackageReference Include="System.Text.Json" Version="7.0.3" />
 	</ItemGroup>
 	<ItemGroup>
 		<None Include="..\..\images\icon.png" Pack="true" Visible="false" PackagePath="" />