chore(deps): update dotnet monorepo to v9

Author: renovate[bot]

Doppler.Extensions/Doppler.Extensions.csproj

@@ -7,8 +7,8 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.Extensions.Configuration.EnvironmentVariables" Version="8.0.0" />
-    <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="8.0.0" />
+    <PackageReference Include="Microsoft.Extensions.Configuration.EnvironmentVariables" Version="9.0.9" />
+    <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="9.0.9" />
     <PackageReference Include="Serilog.Extensions.Hosting" Version="8.0.0" />
     <PackageReference Include="Serilog.Settings.Configuration" Version="8.0.0" />
     <PackageReference Include="Serilog.Sinks.Console" Version="5.0.1" />

global.json

@@ -1,5 +1,5 @@
 {
   "sdk": {
-    "version": "8.0.201"
+    "version": "9.0.305"
   }
 }