Upgrade .NET SDK from 7.402 to 7.403. (#1222)

appveyor.yml

@@ -4,7 +4,7 @@ before_build:
   - nuget restore Renci.SshNet.sln
 
 install:
-  - cinst dotnet-sdk --version=7.0.402 --limit-output
+  - cinst dotnet-sdk --version=7.0.403 --limit-output
 
 build:
   project: Renci.SshNet.sln

global.json

@@ -1,6 +1,6 @@
 {
   "sdk": {
-    "version": "7.0.402",
+    "version": "7.0.403",
     "rollForward": "disable"
   }
 }