Fix useRouteRedirects redirecting to active wallet

[lukaw3d]

useRouteRedirects

This is tough. It was an effect in saga before (https://github.com/oasisprotocol/oasis-wallet-web/blob/5cebb40/src/app/state/wallet/saga.ts#L150) but saga now runs in background page.

One benefit of this is: when you open a popup with stored state, it redirects to your wallet.
One issue is: it always redirects. Even if you have chrome-extension://jplembhokmkioddbchbohdfkmjdmepbb/popup.html#/create-wallet open as a tab, and reload.

Use cases:

• when active wallet changes, redirect to it
• when clicking extension icon to open popup, redirect to active wallet (ideally use history.replace)
  • or (Tadej's preference) clicking extension icon to open popup redirects to last url (ideally use history.replace)
    (conflicts with "not to keep your routes in your Redux store at all" recommendation)
• when reloading an existing popup, don't redirect
• when opening popup with specific URL (e.g. to confirm dapp action), don't redirect

Originally posted by @lukaw3d in #787 (comment)

[lukaw3d]

This will be more annoying after #975

[lukaw3d]

Another issue to check after fixing this:

• create wallet with account1 and account2 (selected)
• open URL of account3
• open account selector and try to open account2 (even tho it is already "selected")
• it shouldn't keep showing account3