Use swiftwasm-release/5.4 for Foundation/XCTest

Author: MaxDesiatov

utils/update_checkout/update-checkout-config.json

@@ -117,8 +117,8 @@
                 "swift-driver": "main",
                 "swift-syntax": "release/5.4",
                 "swift-stress-tester": "release/5.4",
-                "swift-corelibs-xctest": "release/5.4",
-                "swift-corelibs-foundation": "release/5.4",
+                "swift-corelibs-xctest": "swiftwasm-release/5.4",
+                "swift-corelibs-foundation": "swiftwasm-release/5.4",
                 "swift-corelibs-libdispatch": "release/5.4",
                 "swift-integration-tests": "release/5.4",
                 "swift-xcode-playground-support": "release/5.4",