chore(eslint): add missing global comments

These comments tell eslint that those special variables are
globally accessible

Signed-off-by: Philip Molares <philip.molares@udo.edu>

public/js/lib/editor/index.js

@@ -1,3 +1,4 @@
+/* global CodeMirror, inlineAttachment, editor, Cookies  */
 import '@hedgedoc/codemirror-5/addon/comment/comment.js'
 import '@hedgedoc/codemirror-5/addon/comment/continuecomment.js'
 import '@hedgedoc/codemirror-5/addon/dialog/dialog.js'

public/js/lib/editor/utils.js

@@ -1,3 +1,4 @@
+/* global CodeMirror, editor  */
 const wrapSymbols = ['*', '_', '~', '^', '+', '=']
 
 export function wrapTextWith (editor, cm, symbol) {