bump 'marked' to v4

closes #8952

see https://github.com/markedjs/marked/releases/tag/v4.0.0

modules/services/osmose.js

@@ -3,7 +3,7 @@ import RBush from 'rbush';
 import { dispatch as d3_dispatch } from 'd3-dispatch';
 import { json as d3_json } from 'd3-fetch';
 
-import marked from 'marked';
+import { marked } from 'marked';
 
 import { fileFetcher } from '../core/file_fetcher';
 import { localizer } from '../core/localizer';

modules/ui/field_help.js

@@ -2,7 +2,7 @@ import {
     select as d3_select
 } from 'd3-selection';
 
-import marked from 'marked';
+import { marked } from 'marked';
 import { t, localizer } from '../core/localizer';
 import { svgIcon } from '../svg/icon';
 import { icon } from './intro/helper';

modules/ui/panes/help.js

@@ -1,4 +1,4 @@
-import marked from 'marked';
+import { marked } from 'marked';
 import { svgIcon } from '../../svg/icon';
 import { uiIntro } from '../intro/intro';
 import { uiPane } from '../pane';

modules/ui/settings/custom_background.js

@@ -1,5 +1,5 @@
 import { dispatch as d3_dispatch } from 'd3-dispatch';
-import marked from 'marked';
+import { marked } from 'marked';
 
 import { prefs } from '../../core/preferences';
 import { t } from '../../core/localizer';

package.json

@@ -57,7 +57,7 @@
     "fast-deep-equal": "~3.1.1",
     "fast-json-stable-stringify": "2.1.0",
     "lodash-es": "~4.17.15",
-    "marked": "~2.0.0",
+    "marked": "~4.0.12",
     "node-diff3": "3.1.0",
     "osm-auth": "1.1.1",
     "pannellum": "2.5.6",