Fix path

Author: fredrikekre

.buildkite/pipeline.yml

@@ -4,7 +4,7 @@ steps:
     command: |
       # Linux x86_64
       OS=linux ARCH=x86_64 \
-          buildkite-agent pipeline upload ./runtests.yml
+          buildkite-agent pipeline upload ./.buildkite/runtests.yml
     agents:
       queue: "julia"
       os: "linux"