feat(fabric.Canvas) can fire both middle click and right click on canvas

[asturur]

If the user generate a mouse up with 2 buttons, fire both events.

close #6795

[github-actions]

Code Coverage Summary

> [email protected] coverage:report /home/runner/work/fabric.js/fabric.js
> nyc report --reporter=lcov --reporter=text

-----------|---------|----------|---------|---------|-----------------------------------------------
File       | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s                             
-----------|---------|----------|---------|---------|-----------------------------------------------
All files  |   83.32 |    77.05 |   86.12 |   83.03 |                                               
 fabric.js |   83.32 |    77.05 |   86.12 |   83.03 | ...,29999,30124,30204-30269,30392,30491,30708 
-----------|---------|----------|---------|---------|-----------------------------------------------