fix(ssr): fix suspense hydration of fallback content (#7188)

Author: edison1105

packages/runtime-core/src/components/Suspense.ts

@@ -464,7 +464,7 @@ function createSuspenseBoundary(
     timeout: typeof timeout === 'number' ? timeout : -1,
     activeBranch: null,
     pendingBranch: null,
-    isInFallback: true,
+    isInFallback: !isHydrating,
     isHydrating,
     isUnmounted: false,
     effects: [],