[wasm] Fix property name for Emscripten manifest nuget (#55444)

.. this allows the version to get updated in `eng/Versions.props` also,
when updates flow in.

- And update the version to match Version.Details.xml

eng/Versions.props

@@ -180,7 +180,7 @@
     <runtimeosx1012x64MicrosoftNETCoreRuntimeMonoLLVMSdkVersion>11.1.0-alpha.1.21357.1</runtimeosx1012x64MicrosoftNETCoreRuntimeMonoLLVMSdkVersion>
     <runtimeosx1012x64MicrosoftNETCoreRuntimeMonoLLVMToolsVersion>11.1.0-alpha.1.21357.1</runtimeosx1012x64MicrosoftNETCoreRuntimeMonoLLVMToolsVersion>
     <!-- emscripten / Node -->
-    <MicrosoftNETWorkloadEmscriptenManifest60100>6.0.0-preview.7.21355.1</MicrosoftNETWorkloadEmscriptenManifest60100>
-    <MicrosoftNETRuntimeEmscriptenVersion>$(MicrosoftNETWorkloadEmscriptenManifest60100)</MicrosoftNETRuntimeEmscriptenVersion>
+    <MicrosoftNETWorkloadEmscriptenManifest60100Version>6.0.0-preview.7.21358.1</MicrosoftNETWorkloadEmscriptenManifest60100Version>
+    <MicrosoftNETRuntimeEmscriptenVersion>$(MicrosoftNETWorkloadEmscriptenManifest60100Version)</MicrosoftNETRuntimeEmscriptenVersion>
   </PropertyGroup>
 </Project>