fix: imports in custom plugins

Author: Nazarii Mykhailets

@theme/plugins/blog-posts.js

@@ -1,6 +1,6 @@
 // @ts-check
 
-import { getInnerText } from '@redocly/realm/dist/shared/markdoc.js';
+import { getInnerText } from '@redocly/realm/dist/server/plugins/markdown/markdoc/helpers/get-inner-text.js';
 
 import { dirname, relative, join as joinPath } from 'path';
 import markdoc from '@markdoc/markdoc';

@theme/plugins/code-samples.js

@@ -1,6 +1,6 @@
 // @ts-check
 
-import { getInnerText } from '@redocly/realm/dist/shared/markdoc.js';
+import { getInnerText } from '@redocly/realm/dist/server/plugins/markdown/markdoc/helpers/get-inner-text.js';
 
 import { dirname, relative, join as joinPath } from 'path';