Featuretools builds features using index column with Equal and NotEqual primitives

Featuretools builds features using index column with Equal and NotEqual primitives

#### Code Sample, a copy-pastable example to reproduce your bug.

```python
import pandas as pd
import featuretools as ft

df = pd.DataFrame({
"id": [0, 1, 2, 3],
"vals": [100, 1, 2, 3],
})

es = ft.EntitySet()
es.add_dataframe(dataframe_name="df", dataframe=df, index="id", make_index=False)

fm, _ = ft.dfs(entityset=es, target_dataframe_name="df", trans_primitives=["equal", "not_equal"])
fm
```
```
vals id = vals id != vals
id
0 100 False True
1 1 True False
2 2 True False
3 3 True False
```

In the example above, I would not expect any features using the `id` index column to be present in the output feature matrix.

This is likely related to #1851 and happens because we allow comparison between columns with schemas of `` and ``