fix(tile): slotted content renders within the border (#9359)

**Related Issue:** #9358

## Summary

This PR fixes an issue where slotted image content would overflow beyond
the boundary of a `calcite-tile`. Slotted content is now set to take the
full width of the container, regardless of its size on its own. This
will keep visual overflow from happening, and allow developers to
control the sizing of tiles with simple CSS selectors targeting the
`calcite-tile` element.