Adding a special case to _common so that Data Ops get a more informative message

[rcap107]

I added a check to the dispatch module so that if it gets passed a Data Op a more specific error message is shown.
This should address #1477

With this,

import skrub
import pandas as pd

df = pd.DataFrame({"value": [12,3]})

v = skrub.var("data", df)

skrub.TableReport(v)

gets the message

TypeError: Operation not supported on DataOps. Expecting a Pandas or Polars object, but got a DataOp. You may want to use `.skb.eval()` to evaluate the DataOp and obtain a dataframe.

[GaelVaroquaux]

Need to change this :)

[jeromedockes]

thank you @rcap107 !