Add tooltip to table cells with content overflow

[mrvisscher]

Enables users to view a table cell's contents by hovering their pointer over the table cell. If there is an overflow in said cell (i.e. the text is wrapped / cut short with a ...) the full text is shown in a tooltip.

• closes All tables: show full cell content as tooltip on hover #1101

Screenshot of Feature

Notes

• This doesn't apply to headers of tables.
• This will overrule other tooltips set higher in the qt hierarchy, but only if there is an overflow of the table cell in question.

Checklist

• Keep pull requests small so they can be easily reviewed.
• Update the documentation, please follow the numpy style guide
• Update tests.
• Categorize the PR by setting a good title and adding one of the labels:
  bug, feature, ui, change, documentation, breaking, ci
  as they show up in the changelog
• Link this PR to related issues by using closing keywords.
• Request a review from another developer.

[coveralls]

coverage: 50.051% (-0.02%) from 50.066%
when pulling 07cd9ef on mrvisscher:table-tooltip
into c722b17 on LCA-ActivityBrowser:master.

[marc-vdm]

Looking great!

[github-actions]

This issue has been implemented in the new release of Activity Browser 🚀 (version 2.9.3), you can get the new version by updating Activity Browser.

🤖beep boop! I'm a bot and this message was an automated action. If updating does not make sense for this issue, just ignore this.