Fix typo in "Extending Draftail" docs (#10185)

Co-authored-by: Thibaud Colas <thibaudcolas@gmail.com>

CHANGELOG.txt

@@ -36,6 +36,7 @@ Changelog
  * Docs: Ensure search autocomplete overlay on mobile does not overflow the viewport (Ayman Makroo)
  * Docs: Improve documentation for InlinePanel (Vallabh Tiwari)
  * Docs: Add contributor guidelines for building Stimulus Controllers (Thibaud Colas, Loveth Omokaro, LB (Ben) Johnston)
+ * Docs: Fix typo in "Extending Draftail" documentation (Hans Kelson)
  * Maintenance: Removed features deprecated in Wagtail 3.0 and 4.0 (Matt Westcott)
  * Maintenance: Update djhtml (html formatting) library to v 1.5.2 (Loveth Omokaro)
  * Maintenance: Re-enable `strictPropertyInitialization` in tsconfig (Thibaud Colas)

CONTRIBUTORS.rst

@@ -696,6 +696,7 @@ Contributors
 * Himanshu Garg
 * Christopher Wardle
 * Jatin Kumar
+* Hans Kelson
 
 Translators
 ===========

docs/extending/extending_draftail.md

@@ -142,7 +142,7 @@ Here are the main requirements to create a new entity feature:
 -   Like for inline styles and blocks, set up the to/from DB conversion.
 -   The conversion usually is more involved, since entities contain data that needs to be serialised to HTML.
 
-To write the React components, Wagtail exposes its own React, Draft.js, and Draftail dependencies as global variables. Read more about this in [ectending clientside components](extending_clientside_components).
+To write the React components, Wagtail exposes its own React, Draft.js, and Draftail dependencies as global variables. Read more about this in [extending clientside components](extending_clientside_components).
 To go further, please look at the [Draftail documentation](https://www.draftail.org/docs/formatting-options) as well as the [Draft.js exporter documentation](https://github.com/springload/draftjs_exporter).
 
 Here is a detailed example to showcase how those tools are used in the context of Wagtail.

docs/releases/5.0.md

@@ -54,6 +54,7 @@ Support for adding custom validation logic to StreamField blocks has been formal
  * Improve documentation for InlinePanel (Vallabh Tiwari)
  * Remove confusing `SettingsPanel` reference in the page editing `TabbedInterface` example as `SettingsPanel` no longer shows anything as of 4.1 (Kenny Wolf, Julian Bigler)
  * Add contributor guidelines for building [Stimulus Controllers](ui_guidelines_stimulus) (Thibaud Colas, Loveth Omokaro, LB (Ben) Johnston)
+ * Fix typo in "Extending Draftail" documentation (Hans Kelson)
 
 ### Maintenance