Move period before external link icon

Places the period before the external link icon for better visual
flow and readability.

Fixes #64374

Author: burtrw

src/wp-admin/includes/media.php

@@ -3238,7 +3238,7 @@ function edit_form_image_editor( $post ) {
 
 		printf(
 			/* translators: 1: Link to tutorial, 2: Additional link attributes, 3: Accessibility text, 4: External link icon. */
-			__( 'Alt text describes the image\'s purpose. Leave it blank if the image is purely decorative. <a href="%1$s" %2$s>Learn more about alt text%3$s</a>%4$s.' ),
+			__( 'Alt text describes the image\'s purpose. Leave it blank if the image is purely decorative. <a href="%1$s" %2$s>Learn more about alt text%3$s</a>.%4$s' ),
 			/* translators: Localized tutorial, if one exists. W3C Web Accessibility Initiative link has list of existing translations. */
 			esc_url( __( 'https://www.w3.org/WAI/tutorials/images/decision-tree/' ) ),
 			'target="_blank"',

src/wp-includes/media-template.php

@@ -158,7 +158,7 @@ function wp_print_media_templates() {
 
 	$alt_text_description = sprintf(
 		/* translators: 1: Link to tutorial, 2: Additional link attributes, 3: Accessibility text, 4: External link icon. */
-		__( 'Alt text describes the image\'s purpose. Leave it blank if the image is purely decorative. <a href="%1$s" %2$s>Learn more about alt text%3$s</a>%4$s.' ),
+		__( 'Alt text describes the image\'s purpose. Leave it blank if the image is purely decorative. <a href="%1$s" %2$s>Learn more about alt text%3$s</a>.%4$s' ),
 		/* translators: Localized tutorial, if one exists. W3C Web Accessibility Initiative link has list of existing translations. */
 		esc_url( __( 'https://www.w3.org/WAI/tutorials/images/decision-tree/' ) ),
 		'target="_blank"',