chore: Format canbench output so diffs can be seen more easily (#257)

Since Github does not support colored text, I chose to use colored
emojis.

Demo:
<img width="408" alt="Screenshot 2024-12-02 at 17 25 12"
src="https://github.com/user-attachments/assets/9588c9ea-e2ec-48b4-8289-59b38ce829f7">

scripts/ci_run_benchmark.sh

@@ -69,12 +69,17 @@ if [ -f "$MAIN_BRANCH_RESULTS_FILE" ]; then
   fi
 fi
 
+# Add emojis for visualization (as of December 2024, Github does not support colored text)
+FORMATTED_CANBENCH_OUTPUT=$(cat "$CANBENCH_OUTPUT" \
+                            | sed -E 's/.*improved.*/\0 🟢/g' \
+                            | sed -E 's/.*regress.*/\0 🔴/g')
+
 ## Add the output of canbench to the file.
 {
   echo "$UPDATED_MSG"
   echo ""
   echo "\`\`\`"
-  cat "$CANBENCH_OUTPUT"
+  echo "$FORMATTED_CANBENCH_OUTPUT"
   echo "\`\`\`"
 } >> "$COMMENT_MESSAGE_PATH"