Use a more stable sorting for the region metadata (#2014)

Sorting region groups based on the numer of regions in the group
generates some unnecessary changes during SDK updates when adding a new
region in a group.

Author: stof

CHANGELOG.md

@@ -22,6 +22,7 @@
 ### Changed
 
 - Apply new CodingStandard from latest php-cs-fixer.
+- Use a more stable sorting for the list of generated region metadata
 
 ## 2.12.0
 

src/LambdaClient.php

@@ -632,6 +632,13 @@ protected function getEndpointMetadata(?string $region): array
                     'signService' => 'lambda',
                     'signVersions' => ['v4'],
                 ];
+            case 'eu-isoe-west-1':
+                return [
+                    'endpoint' => 'https://lambda.eu-isoe-west-1.cloud.adc-e.uk',
+                    'signRegion' => 'eu-isoe-west-1',
+                    'signService' => 'lambda',
+                    'signVersions' => ['v4'],
+                ];
             case 'us-iso-east-1':
             case 'us-iso-west-1':
                 return [
@@ -656,13 +663,6 @@ protected function getEndpointMetadata(?string $region): array
                     'signService' => 'lambda',
                     'signVersions' => ['v4'],
                 ];
-            case 'eu-isoe-west-1':
-                return [
-                    'endpoint' => 'https://lambda.eu-isoe-west-1.cloud.adc-e.uk',
-                    'signRegion' => 'eu-isoe-west-1',
-                    'signService' => 'lambda',
-                    'signVersions' => ['v4'],
-                ];
         }
 
         return [