Add 16M to nightly bench vs SP1 and improve results description (#581)

* Add 16M cycles to nightly bench-vs-sp1

* Show program and device in Slack post

Author: gabrielbosio

.github/scripts/publish_bench_vs.sh

@@ -81,4 +81,4 @@ fi
 
 curl -X POST "$WEBHOOK_URL" \
     -H 'Content-Type: application/json; charset=utf-8' \
-    --data '{"blocks":[{"type":"header","text":{"type":"plain_text","text":"Lambda VM vs SP1 v6 - Nightly Benchmark"}},{"type":"divider"},{"type":"section","text":{"type":"mrkdwn","text":"'"$RESULTS_MRKDWN"'"}}'"$PROJ_SECTION"']}'
+    --data '{"blocks":[{"type":"header","text":{"type":"plain_text","text":"Lambda VM vs SP1 v6 - Nightly Benchmark"}},{"type":"context","elements":[{"type":"mrkdwn","text":"*Program:* Fibonacci  ·  *Device:* CPU"}]},{"type":"divider"},{"type":"section","text":{"type":"mrkdwn","text":"'"$RESULTS_MRKDWN"'"}}'"$PROJ_SECTION"']}'

.github/workflows/bench-vs-nightly.yml

@@ -43,7 +43,7 @@ jobs:
       - name: Run nightly benchmark
         run: |
           bash ./bench_vs/run.sh \
-            --steps 1000000 2000000 4000000 8000000 \
+            --steps 1000000 2000000 4000000 8000000 16000000 \
             --report-dir bench_vs_artifacts \
             --no-color