SecureMemoryTests.cs: Try to fix another GitHub Actions test failure.

Not enough memory was being allocated to fail on macOS. Hopefully this is enough.

src/Geralt.Tests/SecureMemoryTests.cs

@@ -99,7 +99,7 @@ public void LockMemory_UnlockAndZeroMemory_Invalid(int bufferSize)
     [TestMethod]
     public void LockMemory_UnlockAndZeroMemory_InvalidOperation()
     {
-        var b = new byte[SecureMemory.PageSize * 65536];
+        var b = new byte[SecureMemory.PageSize * 131072];
 
         Assert.ThrowsException<OutOfMemoryException>(() => SecureMemory.LockMemory(b));
         // This test fails on Linux/macOS - munlock() must not return an error despite no locking taking place