Improve replace change method label for multi-value fields

Problem/Motivation

The Replace change method label is currently the same for both single- and multi-value fields, which may cause confusion. For multi-value fields, Replace actually overwrites all existing values, not just one.

Steps to reproduce

Apply replace method for multi-value field.

Proposed resolution

Update the label logic in BulkEditFormTrait to:

• Keep the existing Replace the current value label for single-value fields.
• Use a clearer label Replace all of the current values for multi-value fields.

This distinction helps content editors better understand the effect of bulk edit operations, especially when working with fields that support multiple values.