Update bug-report.yaml (#5220)

Author: RDMacLachlan

.github/ISSUE_TEMPLATE/bug-report.yaml

@@ -35,7 +35,7 @@ body:
       label: NuGet package version
       description: Specify the version of Windows App SDK (or Project Reunion) you're using.
       options:
-        - "Windows App SDK 1.6.3: 1.6.250108002"
+        - "Windows App SDK 1.6.6: 1.6.250228001"
         - "Windows App SDK 1.7 Preview 1: 1.7.250208002-preview1"
         - "Windows App SDK 1.7 Experimental 3: 1.7.250127003-experimental3"
   - type: dropdown