Added token cache reset interval of one week

[amirsaran3]

A large amount of users are raising an issue that they can't see fungible tokens in their near wallet. Indexer and RPC endpoints are returning the tokens correctly, but the issue is still there. There is a big chance that it the problem with the near wallet caching not updating properly.

I added a cache reset for every week so that the cache is synced with the blockchain.

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[MaximusHaximus]

If I'm reading this correctly, this change will only reset the cache if it hasn't been updated for a week -- in the case of a poisoned cache, it may be updated regularly but still invalid -- we want to intermittently clear the cache even if we've updated it regularly and recently. To accomplish this, we will need to set a separate timestamp to track the age of the cache since originally created, then check against that value instead of the last updated timestamp.

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👷 Deploy request for unrivaled-zabaione-2fe19c pending review.

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[amirsaran3]

If I'm reading this correctly, this change will only reset the cache if it hasn't been updated for a week -- in the case of a poisoned cache, it may be updated regularly but still invalid -- we want to intermittently clear the cache even if we've updated it regularly and recently. To accomplish this, we will need to set a separate timestamp to track the age of the cache since originally created, then check against that value instead of the last updated timestamp.

Updated accordingly.

[MaximusHaximus]

Just 2 changes, then this is ready to go.

[AmmarHumackicSQA]

Hey @andy-haynes , would you mind checking this PR from before? Thanks!