fix(ci): repair invalid workflow files (ci.yml + playground.yml) (#14)

* fix(ci): remove empty checkout 'with' and install net8 + net10 runtimes

* test: sample padding-band pixel in WbReceipt background test for cross-platform stability

* fix(ci): remove empty checkout 'with' in playground workflow

Author: RoboNET

.github/workflows/ci.yml

@@ -18,12 +18,13 @@ jobs:
 
     steps:
       - uses: actions/checkout@v4
-        with:
 
       - name: Setup .NET
         uses: actions/setup-dotnet@v4
         with:
-          dotnet-version: '10.0.x'
+          dotnet-version: |
+            8.0.x
+            10.0.x
 
       - name: Restore
         run: dotnet restore FlexRender.slnx

.github/workflows/playground.yml

@@ -31,7 +31,6 @@ jobs:
 
     steps:
       - uses: actions/checkout@v4
-        with:
 
       - name: Setup .NET
         uses: actions/setup-dotnet@v4

tests/FlexRender.Tests/Integration/WbReceiptIntegrationTests.cs

@@ -107,8 +107,10 @@ public async Task WbReceipt_TextWithBackgroundButton_Renders()
 
         Assert.Null(exception);
 
-        // The text background should be black
-        var pixel = bitmap.GetPixel(10, 15);
+        // A pixel inside the element's top-left padding band must be the black
+        // background (padding is 8px, so (2,2) is inside the box but never covered
+        // by a glyph — glyphs are inset by the padding per the box model).
+        var pixel = bitmap.GetPixel(2, 2);
         Assert.Equal(0, pixel.Red);
         Assert.Equal(0, pixel.Green);
         Assert.Equal(0, pixel.Blue);