[pgAdmin4][Patch]: RM#1432 - File Browser - File does not exist error

Hi

Please find the patch with issue fixed:
File Browser - File does not exist error

> it is due to wrong path formation. strip the leftmost slash only from the
> file name selected not from the full path.

Please review.

*Reply to the comments:*
The file browser is virtually unreadable (see screen shot), it does not
work like Mac app
It seems to be font issue to me. I will fix it and send a patch.

When I click on the folder name, it offers to change the folder name
instead of opening it (opening works when I click on the folder logo)
we are performing two operations on double click:
1) Navigate inside the folder
double clicking on folder icon allows to navigate inside the folder.
2) Rename folder
double clicking on folder name allows to rename the file/folder.

When I manage to navigate to the right file and want to open it, I get a
red message ‘File does not exist’. That message disappears after 2-3 seconds
attached a patch with fix.

Thanks,
Surinder Kumar