Fix index access (#29)

Author: zefir-git

src/DocumentComponent.ts

@@ -33,7 +33,7 @@ export class DocumentComponent extends NodeComponent<DocumentFragment> {
         const nodes: NodeComponent<any>[] = [];
         const doc = new DocumentComponent(strings.reduce((acc, str, index) => {
             if (index >= components.length) return acc + str;
-            const component = components[index - 1];
+            const component = components[index];
             if (component instanceof NodeComponent) {
                 nodes.push(component);
                 return `${acc}${str}<slot name="${idPrefix}${nodes.length - 1}"></slot>`;