`-jsconsole` somehow prevented Zotero sources from showing up in the
Debugger tab of the Browser Toolbox, but there's no reason to show the
Browser Console when we're showing the Browser Toolbox, so just don't
pass `-jsconsole` when `d` is passed.
Fixes#4503
Since -jsdebugger apparently works fine, there's no reason to connect to
Zotero from Firefox anymore. So just open the Browser Toolbox when
passing the -d flag to build_and_run, and stop having the devtools
server listen on port 6100 for devtools-enabled builds, since
-jsdebugger uses a random port of its own.
