[Time Tracking] Add the ability to create time expenses

[grgia]

Doc Section

Add time expenses to creation menu

• Gated by Policy settings & Beta

@mhawryluk I've left this issue open so we can discuss if / how you'd like to break the section down into PRs.

[mhawryluk]

@grgia I see this being divided into 2 PRs:

1. submitting a new expense directly from a particular workspace's chat/report
2. creating a new expense from the global + button

is this okay? if we want to divide this even further we could first implement just the first step of entering the hour count and then modify the confirmation page in a follow-up PR

[grgia]

@mhawryluk Yes great idea, its good to break down PRs. Do you want me to create any different issues?

[mhawryluk]

that would be great, thanks! so it would be 3 subissues in place of this one:

1. Allow submitting time expense to a workspace report (the confirmation page would still just show editable account and merchant)
2. Allow editing hours count and rate in the expense confirmation page
3. Allow creating time expenses through the global menu "create expense"