convert tabs to spaces to fix improper indentation (#926)

The hover documentation for `interface MarkupContent` isn't aligned; converting tabs to spaces appears to fix its formatting.

Author: hamirmahal

types/src/main.ts

@@ -1886,13 +1886,13 @@ export type MarkupKind = 'plaintext' | 'markdown';
  * ```ts
  * let markdown: MarkdownContent = {
  *  kind: MarkupKind.Markdown,
- *	value: [
- *		'# Header',
- *		'Some text',
- *		'```typescript',
- *		'someCode();',
- *		'```'
- *	].join('\n')
+ *  value: [
+ *    '# Header',
+ *    'Some text',
+ *    '```typescript',
+ *    'someCode();',
+ *    '```'
+ *  ].join('\n')
  * };
  * ```
  *