fix: fillMissingTokenAddress function doesn't work as expected

[NaijaCoderGirl]

Description:

The return conditions in fillMissingTokenAddress incorrectly trigger an exit when token.L1 or token.L2 are null. The intended behavior should only allow an exit if a non-null, non-zeroAddress token.L1 is found, and thus the function exhausts all possibilities before terminating. I believe this was a mistake that went undetected.

Changes:

-       if (!token.L1 || token.L1 !== zeroAddress) return;
+       if (token.L1 && token.L1 !== zeroAddress) return;
...
-       if (!token.L2 || token.L2 !== zeroAddress) return;
+       if (token.L2 && token.L2 !== zeroAddress) return;

Checklist

• I wrote new tests for my new core changes.
• I have successfully ran tests, style checker and build against my new changes locally.
• I have informed the team of any breaking changes if there are any.