Fix nuxeo-tag text content overlapping in nuxeo-data-table-cell

When a nuxeo-data-table is configured to have 5+ columns, cells for Documents with a large amount of entries for a multi-valued Directory field (e.g. dc:subjects) don't scale to accommodate, resulting in nuxeo-tag text content overlapping with one another.

Steps to reproduce:

1. In Web UI, create a Document and populate the dc:subjects property with at least 5+ entries.
2. Using the default Search drawer item, query for the newly-created document.
3. From the results table settings, make the Subjects column visible and reveal columns until the number visible is at least 5
   • For example: Title, Modified, Last contributor, Version, Subjects
4. Observe the contents of the Subjects column

Expected behavior: the entries for dc:subjects do not overlap. The data table cell scales vertically/horizontally to accommodate the large amount of nuxeo-tag elements.

Actual behavior: the entries for dc:subjects overlap one another, obscuring text content.