Bug#866216: sync Usage with SYNOPSIS

[積丹尼 Dan Jacobson]

Package: epiphany-browser
Version: 3.22.7-1
Severity: minor

$ epiphany --help
Usage:
  epiphany [OPTION…] URL …

But the man page only has

SYNOPSIS
       epiphany [OPTION...] [url]

So the man page should add the dots to show there can be more than one URL,
       epiphany [OPTION...] [url...]

And the --help should add the brackets to show the URLs are optional,
   epiphany [OPTION…] [URL …]