## What changes were proposed in this pull request?

PR fixes the import issue which breaks udf functions.

The following code snippet throws an error

```
scala> import org.apache.spark.sql.functions._
import org.apache.spark.sql.functions._

scala> import org.apache.spark.sql.expressions._
import org.apache.spark.sql.expressions._

scala> udf((v: String) => v.stripSuffix("-abc"))
<console>:30: error: No TypeTag available for String
       udf((v: String) => v.stripSuffix("-abc"))
```

This PR resolves the issue.

## How was this patch tested?

patch tested with unit tests.

(If this patch involves UI changes, please attach a screenshot; otherwise, remove this)

Author: Subhobrata Dey <sbcd90@gmail.com>

Closes #12458 from sbcd90/udfFuncBreak.