[clang] [clang-tools-extra] [clang][ASTMatchers] Fix `hasArraySize` crash without a size expression (PR #215082)

[Yanzuo Liu via cfe-commits]

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zwuis wrote:

I come up with valid code also causing crash.

```cpp
template <int... Is> void f() {
  new int[]{Is...};
}
```

Please add it to tests.

https://github.com/llvm/llvm-project/pull/215082