notifications: Disable default permission pop up.

[YashRE42]

The issue here was that if the user has not allowed desktop
notifications, the browser would give its own pop up requesting for
permission, this would happen concurrently with zulip's custom green bar
that requests for permission, we would prefer that users interact with
our green bar and so this commit disables the pop up.

This fixes #11504 by removing the cause of the problem.

Testing Plan:
Open firefox, navigate to local env, log in as user 1.
Open chrome, navigate to local env, log in as user 2.
click "i" icon and reset notification permissions to default (ask), allow a reload, confirm that green bar is present. [on chrome]
send message to user 2 from user 1. [from firefox to chrome]

• prior to this, you would see a browser pop up
• after this, that pop up no longer triggers.

repeat in opposite order and confirm everything to be same.

The gifs bellow show manual testing:
chrome-notification-working

chrome-notification-blocked

firefox-notifcations-working

firefox-notification-blocked

some extra testing:
chrome-notification-ask-later

chrome-notification-never-ask-later

firefox-notifcations-ask-later

firefox-notification-never-ask-later

node tests:
I've just restored our previous test cases, but we could possibly increase coverage here by writing more tests, but maybe that would be a good follow up?

[YashRE42]

@timabbott This is good to go, tests are cleared.

[timabbott]

This is great, merged as 9369672, thanks @YashRE42! I'd absolutely love to have better test coverage for this module; it's a very old module written long before we had the node test suite, so test coverage isn't great.

One note: I used an edited version of the text and GIT_AUTHOR_* data from @snickell's original PR description, because I thought the description was cleaner and in any case that seems like the most correct attribution.

Thanks for getting this finished @YashRE42!