[dotnet] - remove ubuntu:noble's ubuntu user capturing 1000 uid & gid

src/dotnet/.devcontainer/Dockerfile

@@ -2,6 +2,15 @@ ARG VARIANT=9.0-bookworm-slim
 FROM mcr.microsoft.com/dotnet/sdk:${VARIANT}
 ENV PATH $PATH:/home/vscode/.dotnet:/home/vscode/.dotnet/tools
 
+ARG VARIANT
+RUN if [ "${VARIANT#*noble}" != "$VARIANT"  ]; then \
+        if id "ubuntu" &>/dev/null; then \
+            echo "Deleting user 'ubuntu'  for $VARIANT" && userdel -f -r ubuntu || echo "Failed to delete ubuntu user for $VARIANT"; \
+        else \
+            echo "User 'ubuntu' does not exist for $VARIANT"; \ 
+        fi; \
+    fi
+
 # clear this environment variable so xml docs from NuGet packages are unpackaged. The default dotnet/sdk image sets it to 'skip'.
 # see https://github.com/dotnet/dotnet-docker/issues/2790
 ENV NUGET_XMLDOC_MODE=

src/dotnet/test-project/test.sh

@@ -29,5 +29,23 @@ check "usr-local-etc-config-does-not-exist" test ! -f "/usr/local/etc/gitconfig"
 
 checkPackageVersion "pwsh" "7.4.4" "PowerShell"
 
+check_ubuntu_user() {
+    if ! id -u ubuntu > /dev/null 2>&1; then
+        echo -e "✔️   User ubuntu does not exist."
+    else
+        echo -e "❌   User ubuntu exists."
+        exit 1;
+    fi
+    echo -e "\n\nList of all users:";
+    cat /etc/passwd;
+}
+
+if grep -q 'VERSION_CODENAME=noble' /etc/os-release; then
+    echo -e "\nThe base image is ubuntu:noble. Checking user Ubuntu.."
+    check "uid" "check_ubuntu_user"
+else
+    echo -e "\nCannot check user Ubuntu. The base image is not ubuntu:noble."
+fi
+
 # Report result
 reportResults