fix: Unsuccessful GutenbergKit requests with app passwords for private Atomic sites (#24747)

* build: Update GutenbergKit ref

* build: Update GutenbergKit version

Author: dcalhoun

Modules/Package.resolved

@@ -55,7 +55,7 @@ let package = Package(
         .package(url: "https://github.com/zendesk/support_sdk_ios", from: "8.0.3"),
         // We can't use wordpress-rs branches nor commits here. Only tags work.
         .package(url: "https://github.com/Automattic/wordpress-rs", revision: "alpha-20250813"),
-        .package(url: "https://github.com/wordpress-mobile/GutenbergKit", from: "0.8.0-alpha.0"),
+        .package(url: "https://github.com/wordpress-mobile/GutenbergKit", from: "0.8.0-alpha.1"),
         .package(
             url: "https://github.com/Automattic/color-studio",
             revision: "bf141adc75e2769eb469a3e095bdc93dc30be8de"