fix: allow onboarding and unlocking wallet without Infura mainnet con…

…nectivity (#23388)

Fixes issue where custom networks are not configurable until after
wallet is unlocked.

## Related issues
- Resolves #23333 
- #22713
- Origin: #20277

ui/components/multichain/network-list-menu/network-list-menu.js

@@ -414,7 +414,7 @@ export const NetworkListMenu = ({ onClose }) => {
             <Text>{t('showTestnetNetworks')}</Text>
             <ToggleButton
               value={showTestNetworks}
-              disabled={currentlyOnTestNetwork || !isUnlocked}
+              disabled={currentlyOnTestNetwork}
               onToggle={handleToggle}
             />
           </Box>
@@ -426,7 +426,6 @@ export const NetworkListMenu = ({ onClose }) => {
           <Box padding={4}>
             <ButtonSecondary
               size={ButtonSecondarySize.Lg}
-              disabled={!isUnlocked}
               startIconName={IconName.Add}
               block
               onClick={() => {

ui/components/multichain/network-list-menu/network-list-menu.test.js

@@ -114,9 +114,9 @@ describe('NetworkListMenu', () => {
     expect(queryByText('Chain 5')).not.toBeInTheDocument();
   });
 
-  it('disables the "Add Network" button when MetaMask is locked', () => {
+  it('enables the "Add Network" button when MetaMask is locked', () => {
     const { queryByText } = render(false, '0x5', 'chain5', false);
-    expect(queryByText('Add network')).toBeDisabled();
+    expect(queryByText('Add network')).toBeEnabled();
   });
 
   it('enables the "Add Network" button when MetaMask is true', () => {