buildDotnetModule: add dontPublish flag (#464749)

pkgs/build-support/dotnet/build-dotnet-module/default.nix

@@ -38,6 +38,7 @@ let
       # Unfortunately, dotnet has no method for doing this automatically.
       # If unset, all executables in the projects root will get installed. This may cause bloat!
       executables ? null,
+      dontPublish ? false,
       # Packs a project as a `nupkg`, and installs it to `$out/share`. If set to `true`, the derivation can be used as a dependency for another dotnet project by adding it to `projectReferences`.
       packNupkg ? false,
       # The packages project file, which contains instructions on how to compile it. This can be an array of multiple project files as well.

pkgs/build-support/dotnet/build-dotnet-module/hook/dotnet-hook.sh

@@ -420,13 +420,15 @@ dotnetInstallPhase() {
     done
   }
 
-  if (( ${#projectFiles[@]} == 0 )); then
-    dotnetPublish
-  else
-    local projectFile
-    for projectFile in "${projectFiles[@]}"; do
-      dotnetPublish "$projectFile"
-    done
+  if [[ -z "${dontPublish-}" ]]; then
+    if (( ${#projectFiles[@]} == 0 )); then
+      dotnetPublish
+    else
+      local projectFile
+      for projectFile in "${projectFiles[@]}"; do
+        dotnetPublish "$projectFile"
+      done
+    fi
   fi
 
   if [[ -n ${packNupkg-} ]]; then