We shouldn't provision emsdk on cross-compiler builds, which don't need it (#50136)

Co-authored-by: Jo Shields <joshield@microsoft.com>

Author: github-actions[bot]

src/mono/mono.proj

@@ -94,7 +94,7 @@
 
   <!-- Sets up emscripten if you don't have the EMSDK_PATH env variable set -->
   <Target Name="ProvisionEmscripten"
-          Condition="'$(ShouldProvisionEmscripten)' == 'true'">
+          Condition="'$(ShouldProvisionEmscripten)' == 'true' and '$(SkipMonoCrossJitConfigure)' != 'true'">
     <ReadLinesFromFile File="$(MSBuildThisFileDirectory)\wasm\emscripten-version.txt">
       <Output TaskParameter="Lines" ItemName="_VersionLines" />
     </ReadLinesFromFile>