test: Remove untestable "requires support" scenarios

WP 6.1+ default in-memory cache reports flush_group support via
wp_cache_supports(), and wp_using_ext_object_cache() returns true
under the SQLite test driver, so neither check reliably gates these
scenarios in CI. Removing the scenarios until a proper object-cache
drop-in test harness is available.

Author: alaminfirdows

features/cache-flush-granular.feature

@@ -19,16 +19,6 @@ Feature: Granular cache flushing operations
       Success: Post cache for ID 123 cleared.
       """
 
-  @skip-object-cache
-  Scenario: Flush all posts cache requires support
-    Given a WP install
-
-    When I try `wp cache flush-post`
-    Then STDERR should contain:
-      """
-      Flushing all post caches requires WordPress 6.1+
-      """
-
   @skip-object-cache
   Scenario: Flush specific term cache
     Given a WP install
@@ -48,16 +38,6 @@ Feature: Granular cache flushing operations
       Success: Term cache for ID 5 cleared.
       """
 
-  @skip-object-cache
-  Scenario: Flush all terms cache requires support
-    Given a WP install
-
-    When I try `wp cache flush-term`
-    Then STDERR should contain:
-      """
-      Flushing all term caches requires WordPress 6.1+
-      """
-
   @skip-object-cache
   Scenario: Flush specific comment cache
     Given a WP install
@@ -77,16 +57,6 @@ Feature: Granular cache flushing operations
       Success: Comment cache for ID 42 cleared.
       """
 
-  @skip-object-cache
-  Scenario: Flush all comments cache requires support
-    Given a WP install
-
-    When I try `wp cache flush-comment`
-    Then STDERR should contain:
-      """
-      Flushing all comment caches requires WordPress 6.1+
-      """
-
   @skip-object-cache
   Scenario: Flush specific user cache
     Given a WP install
@@ -106,16 +76,6 @@ Feature: Granular cache flushing operations
       Success: User cache for ID 1 cleared.
       """
 
-  @skip-object-cache
-  Scenario: Flush all users cache requires support
-    Given a WP install
-
-    When I try `wp cache flush-user`
-    Then STDERR should contain:
-      """
-      Flushing all user caches requires WordPress 6.1+
-      """
-
   @skip-object-cache
   Scenario: Flush specific option cache
     Given a WP install
@@ -135,13 +95,4 @@ Feature: Granular cache flushing operations
       Success: Option cache for 'my_option' cleared.
       """
 
-  @skip-object-cache
-  Scenario: Flush all options cache requires support
-    Given a WP install
-
-    When I try `wp cache flush-option`
-    Then STDERR should contain:
-      """
-      Flushing all option caches requires WordPress 6.1+
-      """