ci: Add net462 and net48 to tests

Author: thygesteffensen

.github/workflows/build.yml

@@ -13,7 +13,7 @@ jobs:
     name: Testing
     strategy:
       matrix:
-        dotnet: [ 'netcoreapp3.1', 'net6.0', 'net7.0' ]
+        dotnet: [ 'netcoreapp3.1', 'net6.0', 'net7.0', 'net462', 'net48' ]
     steps:
       - name: Checkout code base
         uses: actions/checkout@v2
@@ -30,7 +30,7 @@ jobs:
     name: Building
     strategy:
       matrix:
-        dotnet: [ 'netcoreapp3.1', 'net6.0', 'net7.0' ]
+        dotnet: [ 'netcoreapp3.1', 'net6.0', 'net7.0', 'net462', 'net48' ]
     steps:
       - name: Checkout code base
         uses: actions/checkout@v2

.github/workflows/release.yml

@@ -12,7 +12,7 @@ jobs:
     name: Testing
     strategy:
       matrix:
-        dotnet: [ 'netcoreapp3.1', 'net6.0', 'net7.0' ]
+        dotnet: [ 'netcoreapp3.1', 'net6.0', 'net7.0', 'net462', 'net48' ]
     steps:
       - name: Checkout code base
         uses: actions/checkout@v2