Twenty Seventeen: Document the the_content filter.

Adds documentation references to the filter's docblock in `wp-includes/post-template.php`.

Follow-up to [38833].

Props pmbaldha, mukesh27, sabernhardt.
Fixes #63637.

Built from https://develop.svn.wordpress.org/trunk@60430


git-svn-id: http://core.svn.wordpress.org/trunk@59766 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-content/themes/twentyseventeen/template-parts/post/content-audio.php

@@ -42,6 +42,7 @@
 	</header><!-- .entry-header -->
 
 	<?php
+		/** This filter is documented in wp-includes/post-template.php */
 		$content = apply_filters( 'the_content', get_the_content() );
 		$audio   = false;
 

wp-content/themes/twentyseventeen/template-parts/post/content-video.php

@@ -42,6 +42,7 @@
 	</header><!-- .entry-header -->
 
 	<?php
+		/** This filter is documented in wp-includes/post-template.php */
 		$content = apply_filters( 'the_content', get_the_content() );
 		$video   = false;
 

wp-includes/version.php

@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.9-alpha-60429';
+$wp_version = '6.9-alpha-60430';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.