[BUG] Confusing cancel button flow for visualization plugin

[abbyhu2000]

Describe the bug
As documented in the comments in this PR, #2627, It seems like the original cancel flow for visualization plugin is quite confusing and unnecessarily complicated:

1. When user create viz from visualization page, no cancel button is shown
2. When user edit viz from visualization page, no cancel button is shown
3. When user tries to create viz from dashboard page, cancel button is shown
4. When user create viz from dashboard with add to dashboard after saving toggle off, then click save. It will direct back to the vis editor page, cancel button is not shown
5. When user edit viz from dashboard page, cancel button is shown
6. When user edit viz from dashboard page, made some changes, click save as. Toggle save as new visualization on, and add to dashboard after saving off, cancel button is not shown
7. When user edit viz from dashboard page, made some changes, click save as. Toggle save as new visualization off, and add to dashboard after saving off, cancel button is shown

I think we should rework and simplify the cancel flow for the visualization plugin so we could have a unified cancel flow throughout the app, ex. vis builder plugin.

One cancel flow can be:

1. cancel button will not be shown when user creates or edits vis builder from visualization page
2. cancel button will always be shown when user creates or edits vis builder from the dashboard page.