[NAVREDESIGN] Account Switcher Component

### **Description**

Create `Account Switcher` component for opening `AccountSwitcher` screen

### **Technical Details**

- This component is essentially a button
- Consumes data from redux with account information
- Renders icons and label based on whatever account(s) is selected
- Only additional logic would be to handle rendering all accounts

### **Acceptance Criteria**

- TBD

### **References**

- Figma - https://www.figma.com/file/qcwJHEEw5qyNru5mbFf6Oq/Nav-Redesign-Breakdown?node-id=101%3A629
- ETA - 2 Days

Start with the Figma Account Switcher reference and locate the existing AccountSwitcher screen and navigation entry point. Read the Redux account data used by nearby navigation components, then verify the new button renders the selected account icon and label, supports multiple accounts, and opens AccountSwitcher. Acceptance criteria are currently TBD.

Written by the indexing model from the issue text.