disabling workbench transitions without a selection

[dvzacharycutler]

Closes https://github.com/datavisyn/reprovisyn/issues/492

Developer Checklist (Definition of Done)

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• [x] All acceptance criteria from the issue are met
• [x] Branch is up-to-date with the branch to be merged with, i.e., develop
• [x] Code is cleaned up and formatted
• [x] Code documentation written
• [ ] Unit tests written
• [x] Tested in Chrome
• [x] Tested in Firefox
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Summary of changes

• Disabling workbench transitions if no items are selected. Disabled by just reducing opacity, can increase it more/less if you want. Also changing the cursor to signify it is disabled, and adding a hover (via title) explaining that a row needs to be selected

I would like to also mention I do not think this change is actually necessary. I don't see any problem with someone making a transition even if they don't have a selection, so don't see a purpose in making it impossible. Seems to simply be unnecessarily restrictive.

Screenshots

https://user-images.githubusercontent.com/87644761/181244773-2bccaf46-965e-4a21-9a1f-a6a99975c3ed.mp4