[CQ] migrate off slated-for-removal SystemInfo access (#8653)

<img width="2706" height="244" alt="image" src="https://github.com/user-attachments/assets/5c9bf160-0793-4943-94ea-eef30a713580" />

https://plugins.jetbrains.com/plugin/9212-flutter/edit/versions/dev/909537#verification-results

I'm pretty sure this is behavior-preserving but could use another set of eyes.

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Author: pq

src/io/flutter/utils/JxBrowserUtils.java

@@ -25,18 +25,22 @@ public String getPlatformFileName() throws FileNotFoundException {
     String name = "";
     final boolean is64Bit = Objects.requireNonNull(CpuArch.CURRENT).width == 64;
     if (SystemInfo.isMac) {
-      if (SystemInfo.isAarch64){
+      if (CpuArch.isArm64()) {
         name = "mac-arm";
-      } else {
+      }
+      else {
         name = "mac";
       }
-    } else if (SystemInfo.isWindows) {
+    }
+    else if (SystemInfo.isWindows) {
       if (CpuArch.is32Bit()) {
         name = "win32";
-      } else if (is64Bit) {
+      }
+      else if (is64Bit) {
         name = "win64";
       }
-    } else if (SystemInfo.isLinux && is64Bit) {
+    }
+    else if (SystemInfo.isLinux && is64Bit) {
       name = "linux64";
     }