p-calendar: Pressing Enter key on prev or next month arrows calls onPrevButtonClick or onNextButtonClick twice respectively

[mir4ef]

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Current behavior
When the enter key is used to navigate between months, it skips a month. For example, if the current month is July and I press the enter key when previous month arrow is focused, the calendar displays May.

Expected behavior
I would expect the calendar to go -1 or +1 month. For example, if the current month is July and I press the enter key when previous month arrow is focused, the calendar should display June. (I think it is worth mentioning that when pressing the space bar key, it functions as expected - it navigates 1 month at a time.)

Minimal reproduction of the problem with instructions
STEPS TO REPRODUCE

1. Add a p-calendar element to an angular html file
2. Set the inline attribute to true
3. Use the keyboard (tab key) to navigate the UI
4. When the previous (or next) month arrow is on focus, press the enter key one time
5. The calendar view navigates -2 (or +2) months instead of -1 (or +1) depending whether you pressed back or forward. For example, if the current month is July and I press the enter key when previous month arrow is focused, the calendar displays May.

MINIMAL DEMO
https://stackblitz.com/edit/github-primeng-calendar?file=src/app/app.component.html

What is the motivation / use case for changing the behavior?
A user cannot use the Enter key to effectively navigate between months because it skips a month when Enter is used.
I think this behavior is caused by the two event listeners on the previous and next buttons - (click) and (keydown.enter). Buttons by default trigger click events when Enter or Space bar are pressed. I am probably missing something and would appreciate any info, but I am not sure what the reason for having an additional listener for Enter key here is.

Please tell us about your environment:
OS: Mac 10.15 and Windows 10
IDE: IntelliJ
Package manager: npm v6.14.8
Http server: nginx and webpack dev server (localhost)

• Angular version: 10.1.5

• PrimeNG version: 10.0.3

• Browser:
  We tested these desktop browsers: [ Chrome 86 | Firefox 82 | IE 11 | Safari 13 ]

• Language: [all]

• Node (for AoT issues): node --version = 14.15.0