docs: Add 'show tree' to the 'Quick Reference' page

Author: claremacrae

docs/Quick Reference.md

@@ -50,6 +50,7 @@ This table summarizes the filters and other options available inside a `tasks` b
 | **[[Filters#Description\|Description]]**, **[[Filters#Tags\|Tags]]** and other odds and ends                                                                                                                                                                                                                                                         |                                             |                        |                        |                                                                                                                                |
 | `description (includes, does not include) <string>`<br>`description (regex matches, regex does not match) /regex/i`                                                                                                                                                                                                                                  | `sort by description`                       |                        |                        | `task.description`<br>`task.descriptionWithoutTags`                                                                            |
 | `has tags`<br>`no tags`<br>`tag (includes, does not include) <tag>`<br>`tags (include, do not include) <tag>`<br>`tag (regex matches, regex does not match) /regex/i`<br>`tags (regex matches, regex does not match) /regex/i`                                                                                                                       | `sort by tag`<br>`sort by tag <tag_number>` | `group by tags`        | `hide tags`            | `task.tags`                                                                                                                    |
+|                                                                                                                                                                                                                                                                                                                                                      |                                             |                        | `show tree`            |                                                                                                                                |
 |                                                                                                                                                                                                                                                                                                                                                      |                                             |                        |                        | `task.originalMarkdown`                                                                                                        |
 |                                                                                                                                                                                                                                                                                                                                                      | `sort by random`                            |                        |                        |                                                                                                                                |
 | **[[About Scripting\|Scripting]]**                                                                                                                                                                                                                                                                                                                   |                                             |                        |                        |                                                                                                                                |