V3 - Add Custom Attributes for Bulk Actions

[lrljoe]

This PR adds several new methods for customising the look & feel of the Bulk Actions "th" "td" and associated checkboxes, methods documented, but summarised as follows:

• setBulkActionsThAttributes(array $bulkActionsThAttributes) You may pass an array to this method, which allows you to pass Custom Attributes into the table header

• setBulkActionsThCheckboxAttributes(array $bulkActionsThCheckboxAttributes) You may pass an array to this method, which allows you to pass Custom Attributes into the Select All/None checkbox in the Table Header

• setBulkActionsTdAttributes(array $bulkActionsTdAttributes) You may pass an array to this method, which allows you to pass Custom Attributes into the td containing the Bulk Actions Checkbox for a row

• setBulkActionsTdCheckboxAttributes(array $bulkActionsTdCheckboxAttributes) You may pass an array to this method, which allows you to pass Custom Attributes into the Bulk Actions Checkbox for the row

### Currently pending test creation.

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[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Comparison is base (db0689d) 88.99% compared to head (b8f623a) 89.07%. Report is 5 commits behind head on develop.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## develop #1564 +/- ## ============================================= + Coverage 88.99% 89.07% +0.07% - Complexity 1268 1276 +8 ============================================= Files 96 96 Lines 3008 3030 +22 ============================================= + Hits 2677 2699 +22 Misses 331 331 ```

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