Bump System.Text.Json from 5.0.1 to 7.0.2 (#2005)

Bumps [System.Text.Json](https://github.com/dotnet/runtime) from 5.0.1 to 7.0.2.
- [Release notes](https://github.com/dotnet/runtime/releases)
- [Commits](dotnet/runtime@v5.0.1...v7.0.2)

---
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>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

src/RestSharp/RestSharp.csproj

@@ -3,7 +3,7 @@
         <EmitCompilerGeneratedFiles>true</EmitCompilerGeneratedFiles>
     </PropertyGroup>
     <ItemGroup Condition="$(TargetFramework) != 'net6.0' And $(TargetFramework) != 'net7.0'">
-        <PackageReference Include="System.Text.Json" Version="5.0.1" />
+        <PackageReference Include="System.Text.Json" Version="7.0.2" />
     </ItemGroup>
     <ItemGroup>
         <None Remove="RestSharp.csproj.DotSettings" />