Added timezone select element to registration page

• Wanted to create a component for this but didn't wanna figure out how to pass data and v-model between the child and parent. So just added the whole block of HTML options into the reg page
• upon registration, I had to in parallel create an `account`, then get the response data in order to then update the `account` id into the `user`'s data:

await this.$axios.post(`endpoint of accounts`).then((res) => {
this.$axios.put(`endpoint of user`, {account: res.id,})})

• upon successful registration, user gets redirected to home page but somehow the sidebar leaderboards were simply not loading. I think the auto-redirect after `this.$auth.loginWith('local',...)` either doesn't trigger $fetch() or mounted(), so the data isn't loading. Had to use a hard refresh `location.reload()` to get the data on the sidebar leaderboards rendering properly. Not elegant, but user likely have to go through this just once in their user lifetime only.
• tweaked TimezoneSelect component in /account page to use new `accounts` endpoint for fetching timezones