test: add new manifests for edge installers

Edge installer manifests (both simplified and anaconda) added for RHEL
8.6, RHEL 9.0, CS8, and CS9 for both supported architectures.

test/data/manifests/centos_9-aarch64-image_installer-boot.json

@@ -21515,4 +21515,4 @@
       }
     ]
   }
-}
+}

test/data/manifests/rhel_86-aarch64-image_installer-boot.json

@@ -20564,4 +20564,4 @@
       }
     ]
   }
-}
+}

test/data/manifests/rhel_90-aarch64-image_installer-boot.json

@@ -20128,4 +20128,4 @@
       }
     ]
   }
-}
+}