fix(deps): tocbot has no initialization detection (#957)

Resolves #957

Author: cotes2020

_javascript/modules/components/toc.js

@@ -1,11 +1,13 @@
 export function toc() {
-  // see: https://github.com/tscanlin/tocbot#usage
-  tocbot.init({
-    tocSelector: '#toc',
-    contentSelector: '.post-content',
-    ignoreSelector: '[data-toc-skip]',
-    headingSelector: 'h2, h3',
-    orderedList: false,
-    scrollSmooth: false
-  });
+  if (document.querySelector('#core-wrapper h2,#core-wrapper h3')) {
+    // see: https://github.com/tscanlin/tocbot#usage
+    tocbot.init({
+      tocSelector: '#toc',
+      contentSelector: '.post-content',
+      ignoreSelector: '[data-toc-skip]',
+      headingSelector: 'h2, h3',
+      orderedList: false,
+      scrollSmooth: false
+    });
+  }
 }