ci(github): add an lttng build

lttng defaults to on, so nothing is required other than installing it
conditionally. Add a build for it.

.github/workflows/distcheck.yaml

@@ -74,6 +74,9 @@ jobs:
         cc:
           - gcc
           - clang
+        tracing:
+          - lttng
+          - none
         sdk:
           - cuda
           - neuron
@@ -150,6 +153,13 @@ jobs:
           packages: aws-neuronx-runtime-lib
           version: neuron-packages
 
+      - name: Install lttng
+        uses: awalsh128/cache-apt-pkgs-action@latest
+        if: matrix.tracing == 'lttng'
+        with:
+          packages: liblttng-ust-dev
+          version: lttng
+
       - name: Install Libfabric
         run: |
           # We're just doing distchecks, so it is fine if we