fix(frontend): prevent crash if redirect param is undefined

[afsuyadi]

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Changes

Contributes to #7524

1. A crash on the home page happens when the URL contains "invite" but has no redirect query parameter, causing invite to be undefined
2. I Added optional chaining (?.) before .includes() calls on the invite variable in HomePage.tsx.

How did you test this code?

1. Navigate to home page with URL containing "invite" but no redirect
2. I try to add console.log message in my local just to see if variable invite has any value
3. I could see the error happens when there is no redirect param in the URL
4. After adding the optional chaining, the error disappears

Before changes:
Screencast from 16-06-26 08:22:04.webm

After changes:
Screencast from 16-06-26 08:48:55.webm

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