FALSE NEGATIVE: NULLPTR_DEREFERENCE misses a null local after a finite loop

Hi, I found a false negative in Infer 1.3.0 when object remains null throughout the finite loop and is dereferenced.

**Affected checker**

`Infer NULLPTR_DEREFERENCE`

**Minimal reproducer**

```java
class InferNullAfterLoop {
void step() {}

void test() {
Object object = null;
for (int index = 0; index < 10; index++) {
step();
}
object.toString();
}
}
```

**Reproduction command**

```bash
infer --version
infer run --pulse --enable-issue-type NULLPTR_DEREFERENCE -- javac infer-nullptr-fn-after-loop.java
```

**Current behavior**

Infer completes successfully but produces no `NULLPTR_DEREFERENCE` finding. Changing the loop bound from 10 to 2 makes Infer report the dereference.

**Expected behavior**

Infer should report `NULLPTR_DEREFERENCE` at line 9 because object remains null throughout the finite loop and is dereferenced.