Fix issue to return to setup after viewing terms of use

[jessgusclark]

What it fixes

Allows the user to click the back button from the Terms of Use page when initially launching the app.

Reasoning

• The property onBackButtonPress() is an internal function of the WebViewModal component. Instead, use the onCloseButtonPress() method that is accessible from the props.
• The internal onBack... method checks if the web component can go back, and if so, it takes the user back a page in the web browser. Perhaps they clicked on the privacy policy and now want to go back to the TOS page.
• When the user clicks on the 'x' button, it fires the onClose... function, which is the expected behavior.

To test

• Uninstall the app to clear the RN storage
• Install, on the tos page, click to "View complete Terms of Use"
• Click Close
• Click "View..." again,
• Click on a link, such as "Privacy Policy", click back button

[sonarqubecloud]

Kudos, SonarCloud Quality Gate passed!

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
0.0% Duplication

[itofarina]

LGTM 👌
Tested on iOS simulator