cmdpal: turn on condition package for cmdpal (#40124)

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- [X] **Closes:** #40103
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- [ ] **Tests:** Added/updated and all pass
- [ ] **Localization:** All end-user-facing strings can be localized
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src/modules/cmdpal/Microsoft.CmdPal.UI/Microsoft.CmdPal.UI.csproj

@@ -23,7 +23,7 @@
     <AppendRuntimeIdentifierToOutputPath>false</AppendRuntimeIdentifierToOutputPath>
   </PropertyGroup>
 
-  <PropertyGroup>
+  <PropertyGroup Condition="'$(CIBuild)'=='true'">
     <GenerateAppxPackageOnBuild>true</GenerateAppxPackageOnBuild>
   </PropertyGroup>