tests/CI: Stop using spread-arm

Not needed anymore now we use new runners.

Signed-off-by: Paul Mars <[email protected]>

.github/workflows/spread-test.yaml

@@ -113,12 +113,10 @@ jobs:
             echo "::add-matcher::.github/spread-problem-matcher.json"
   
             BACKEND=google
-            SPREAD=spread
             SERIES=${{ matrix.series }}
 
             if [[ "${{ matrix.systems }}" =~ -arm- ]]; then
               BACKEND=google-arm
-              SPREAD=spread-arm
             fi
 
             RUN_TESTS=""
@@ -134,8 +132,8 @@ jobs:
             # "pipefail" ensures that a non-zero status from the spread is
             # propagated; and we use a subshell as this option could trigger
             # undesired changes elsewhere
-            echo "Running command: $SPREAD $RUN_TESTS"
-            (set -o pipefail; $SPREAD $RUN_TESTS | tee spread.log)
+            echo "Running command: spread $RUN_TESTS"
+            (set -o pipefail; spread $RUN_TESTS | tee spread.log)
 
       - name: Discard spread workers
         if: always()