[Bug] Disable generate ename button

[grv-saini-20]

Description

make the next button disabled if verification code field is empty. also disabled the button when demo name is empty.

Steps to reproduce

1. Go to app.
2. Click on proceed with pre-verification code.
3. press next button with empty field.
4. See error.

Expected behavior

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Supporting Media

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Desktop:

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• Device: [eg. Mobile/PC]
• OS: [e.g. iOS/Windows]
• Browser: [e.g. chrome, safari]
• Version: [e.g. 22]

Additional Context

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