fix: update TargetFramework to net8.0 in docfx.json

Author: JaCraig

docfx_project/docfx.json

@@ -9,7 +9,7 @@
       ],
       "dest": "api",
       "properties": {
-        "TargetFramework": "net6.0"
+        "TargetFramework": "net8.0"
       },
       "includePrivateMembers": false,
       "disableGitFeatures": false,