CI: Setup net 8, 9 for some jobs on ubuntu-latest (#658)

Author: mpreyskurantov

.github/actions/dotnet-test-build/action.yml

@@ -5,7 +5,7 @@ runs:
   using: "composite"
 
   steps:
-  - uses: actions/setup-dotnet@v3
+  - uses: actions/setup-dotnet@v4
     with:
       dotnet-quality: ga
       dotnet-version: 9.0

.github/workflows/ci.yml

@@ -92,7 +92,9 @@ jobs:
     - uses: actions/setup-dotnet@v4
       with:
         dotnet-quality: ga
-        dotnet-version: 3.1
+        dotnet-version: |
+          3.1
+          8.0
 
     - uses: actions/checkout@v4