Fix debug builds failling because of core lib

Unfortunately the follwing problem was reintroduced because the linux
target was removed without checking if debug builds still worked.

Issue: cross-rs/cross#724

.gitignore

@@ -455,3 +455,7 @@ documentation-build
 
 # Automatically generated native library bindings
 AKL.Common/bindings
+
+# Build artifcats of the debug builds for akl-core-system-lib
+build-win
+build-linux

AKL.Common/AKL.Common.csproj

@@ -57,9 +57,9 @@
       WorkingDirectory="$(MSBuildProjectDirectory)/../akl-core-system-lib" /> 
 
     <!-- Compile debug server -->
-    <Exec Command="cross build --release --target x86_64-pc-windows-gnu --bin debug-server"
+    <Exec Command="cross build --release --target x86_64-pc-windows-gnu --bin debug-server --target-dir build-win"
       WorkingDirectory="$(MSBuildProjectDirectory)/../akl-core-system-lib" /> 
-    <Exec Command="cross build --release --target x86_64-unknown-linux-gnu --bin debug-server"
+    <Exec Command="cross build --release --target x86_64-unknown-linux-gnu --bin debug-server --target-dir build-linux"
       WorkingDirectory="$(MSBuildProjectDirectory)/../akl-core-system-lib" /> 
 
     <!-- Copy generated bindings from the native lib -->
@@ -73,7 +73,7 @@
           <PublishState>Included</PublishState>
           <ExcludeFromSingleFile>true</ExcludeFromSingleFile>
       </Content>
-      <Content Include="../akl-core-system-lib/target/x86_64-pc-windows-gnu/release/debug-server.exe">
+      <Content Include="../akl-core-system-lib/build-win/x86_64-pc-windows-gnu/release/debug-server.exe">
           <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
           <PublishState>Included</PublishState>
           <ExcludeFromSingleFile>true</ExcludeFromSingleFile>