Set version to 5.51.beta1

ext/sequentialcreditnotes/info.xml

@@ -15,7 +15,7 @@
     <url desc="Licensing">http://www.gnu.org/licenses/agpl-3.0.html</url>
   </urls>
   <releaseDate>2020-01-28</releaseDate>
-  <version>5.51.alpha1</version>
+  <version>5.51.beta1</version>
   <tags>
     <tag>mgmt:hidden</tag>
   </tags>

sql/civicrm_generated.mysql

@@ -2938,7 +2938,7 @@ UNLOCK TABLES;
 LOCK TABLES `civicrm_domain` WRITE;
 /*!40000 ALTER TABLE `civicrm_domain` DISABLE KEYS */;
 INSERT INTO `civicrm_domain` (`id`, `name`, `description`, `version`, `contact_id`, `locales`, `locale_custom_strings`) VALUES
- (1,'Default Domain Name',NULL,'5.51.alpha1',1,NULL,'a:1:{s:5:\"en_US\";a:0:{}}');
+ (1,'Default Domain Name',NULL,'5.51.beta1',1,NULL,'a:1:{s:5:\"en_US\";a:0:{}}');
 /*!40000 ALTER TABLE `civicrm_domain` ENABLE KEYS */;
 UNLOCK TABLES;

sql/test_data_second_domain.mysql

@@ -908,4 +908,4 @@ INSERT INTO civicrm_navigation
 VALUES
     ( @domainID, CONCAT('civicrm/report/instance/', @instanceID,'&reset=1'), 'Mailing Detail Report', 'Mailing Detail Report', 'administer CiviMail', 'OR', @reportlastID, '1', NULL, @instanceID+2 );
 UPDATE civicrm_report_instance SET navigation_id = LAST_INSERT_ID() WHERE id = @instanceID;
-UPDATE civicrm_domain SET version = '5.51.alpha1';
+UPDATE civicrm_domain SET version = '5.51.beta1';

xml/version.xml

 <?xml version="1.0" encoding="iso-8859-1" ?>
 <version>
-  <version_no>5.51.alpha1</version_no>
+  <version_no>5.51.beta1</version_no>
 </version>