Login and Registration: Wrap long usernames in login error message.

Adds `word-wrap: break-word` to wrap long usernames in the login's error message. Using `word-wrap` instead of `word-break` for better cross-browser support and to avoid the deprecation (see Ref below).

For consistency, also changes `#backtoblog`.

Ref:
* `word-break: break-word` deprecation https://developer.mozilla.org/en-US/docs/Web/CSS/word-break#syntax

Follow-up to [51108].

Props soniakash, audrasjb, sabernhardt, hellofromTonya, desrosj, ocean90.
Fixes #37617.
Built from https://develop.svn.wordpress.org/trunk@52174


git-svn-id: http://core.svn.wordpress.org/trunk@51766 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/css/login-rtl.css

@@ -51,6 +51,7 @@ p {
 	margin-bottom: 20px;
 	background-color: #fff;
 	box-shadow: 0 1px 1px 0 rgba(0, 0, 0, 0.1);
+	word-wrap: break-word;
 }
 
 .login .success {
@@ -298,7 +299,7 @@ p {
 
 #backtoblog {
 	margin: 16px 0;
-	word-break: break-word;
+	word-wrap: break-word;
 }
 
 .login #nav a,

wp-admin/css/login.css

@@ -50,6 +50,7 @@ p {
 	margin-bottom: 20px;
 	background-color: #fff;
 	box-shadow: 0 1px 1px 0 rgba(0, 0, 0, 0.1);
+	word-wrap: break-word;
 }
 
 .login .success {
@@ -297,7 +298,7 @@ p {
 
 #backtoblog {
 	margin: 16px 0;
-	word-break: break-word;
+	word-wrap: break-word;
 }
 
 .login #nav a,

wp-includes/version.php

@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.9-alpha-52173';
+$wp_version = '5.9-alpha-52174';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.