build: remove output from webui.sh

Unix says: if everything goes well, remain silent.
diff --git a/build/webui.sh b/build/webui.sh
index 356c0e3..46c5e5d 100755
--- a/build/webui.sh
+++ b/build/webui.sh
@@ -1,8 +1,6 @@
 #!/bin/bash
 set -e
 
-echo "[$(date '+%H:%M:%S')] Starting webui build..."
-
 # Use a content-based hash of the webui dir to avoid unnecessary rebuilds.
 OUTPUT_DIR="embedded/webui-dist"
 # go:embed ignores files that start with a '.'
@@ -24,14 +22,10 @@
 if [ -f "$HASH_FILE" ] && [ -d "$OUTPUT_DIR" ]; then
 	STORED_HASH=$(cat "$HASH_FILE")
 	if [ "$CURRENT_HASH" = "$STORED_HASH" ]; then
-		echo "No changes, skipping rebuild"
 		exit 0
 	fi
 fi
 
-echo "[$(date '+%H:%M:%S')] Removing old output directory..."
 rm -rf "$OUTPUT_DIR"
-echo "[$(date '+%H:%M:%S')] Running genwebui..."
 unset GOOS GOARCH && go run ./cmd/genwebui -- "$OUTPUT_DIR"
 echo "$CURRENT_HASH" >"$HASH_FILE"
-echo "[$(date '+%H:%M:%S')] Webui build completed"