Update .gitlab-ci.yml file

.gitlab-ci.yml

@@ -26,7 +26,7 @@ build-job:       # This job runs in the build stage, which runs first.
   script:
     - echo "Compiling the code..."
     - whoami
-    - dotnet
+    - /home/gitlab-runner/.dotnet/dotnet
     - mvn compile
     - echo "Compile complete."