[Bookmarks Plugin] Add custom firefox browser support

[VictoriousRaptor]

Close #1856

Add a combobox in add custom browser dialog to choose browser engine (chromium or Firefox)

Test:

• Firefox bookmarks can be searched by adding data folder path to custom browser

[taooceros]

Nice! Next time mind add a screenshot for the description?

[taooceros]

Please also add the browser type here (should be very easy).

[VictoriousRaptor]

Please also add the browser type here (should be very easy).

Added. Please check.

[VictoriousRaptor]

Deleted the branch accidentally.

[github-actions]

@check-spelling-bot Report

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combobox

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... in a clone of the [email protected]:VictoriousRaptor/Flow.Launcher.git repository
on the SelectBrowserCore branch (ℹ️ how do I use this?):

curl -s -S -L 'https://raw.githubusercontent.com/check-spelling/check-spelling/main/apply.pl' |
perl - 'https://github.com/Flow-Launcher/Flow.Launcher/actions/runs/4140158535/attempts/1'

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[onesounds]

I tested this. There was a moment when it worked, but not after that.
(I installed a browser called librewolf and tested it.)
As I know, Firefox-based browsers store bookmarks in the places.sqlite file. Do I have to designate this?

I checked that it works if I specify a directory.

There is no need to modify it in this pr, but I take notes in case I forget it.

• There is no edit button
• It would be nice to have a guide text to specify a path, not a file.
• It would be nice to have a "browse" button.