(NFC) Make datatables in Activities Relationship tab adjust to screen size

[samuelsov]

Overview

Cosmetic changes to make datatables in Activities and Relationship tab behave like the membership tab, i.e. the table adjust as much as possible to the size of the screen.

Before

In Activities tab, the size is properly initialized but when resizing the window, it keeps the original size:

In Relationship tab, it doesn't initialize properly and doesn't follow the window size:

After

In Activities tab:

In Relationships tab:

Technical Details

Added style="width: 100%; " as suggested in https://datatables.net/examples/basic_init/flexible_width.html

[civibot]

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[samuelsov]

The check fail has nothing to do with the PR, i.e. just in a small UI change.

[eileenmcnaughton]

@mattwire thoughts on this one?

[mattwire]

Ok tested. Before=rubbish. After=better. Please merge

[eileenmcnaughton]

test fails unrelated - merging per @mattwire review