Fixed formatting typo in --purge-only command flag

Was rendering as `-purge-only` (with one dash)
Fixes #11646

CHANGELOG.txt

@@ -15,6 +15,7 @@ Changelog
  * Fix: Prevent crash when loading an empty table block in the editor (Sage Abdullah)
  * Docs: Update Sphinx theme to `6.3.0` with a fix for the missing favicon (Sage Abdullah)
  * Docs: Update broken and incorrect links throughout the documentation (EK303)
+ * Docs: Fix formatting of `--purge-only` in `wagtail_update_image_renditions` management command section (Pranith Beeram)
 
 
 6.0.1 (15.02.2024)

CONTRIBUTORS.md

@@ -792,6 +792,7 @@
 * mirusu400
 * Maikel Martens
 * EK303
+* Pranith Beeram
 
 ## Translators
 

docs/reference/management_commands.md

@@ -166,5 +166,5 @@ This does not remove rendition images that are unused, this can be done by clear
 
 Options:
 
--   **--purge-only** :
+-  `--purge-only` :
     This argument will purge all image renditions without regenerating them. They will be regenerated when next requested.

docs/releases/6.0.2.md

@@ -27,3 +27,4 @@ depth: 1
 
  * Update Sphinx theme to `6.3.0` with a fix for the missing favicon (Sage Abdullah)
  * Update broken and incorrect links throughout the documentation (EK303)
+ * Fix formatting of `--purge-only` in `wagtail_update_image_renditions` management command section (Pranith Beeram)