Zetaclient should be able to remove the timeout logic when iterating thru EVM chain outtx trackers

[ws4charlie]

Describe the Issue
Zetaclient still has the legacy timeout logic in function ObserveOutTx when it iterates thru the outtx tracker list. We should be able to get rid of this legacy logic which was introduced in hotfix patch to deal with overwhelming number of trackers.

The reason is that the EVM chain won't face overwhelming number of trackers in the latest implementation for that

1. Zetaclient looks ahead120 cctx at most, meaning the number of pending trackers will always be <= 120, which is computationally a small list to iterate thru.
2. The latest zetacore, after mainnet, is able to effectively block submission of garbage trackers (for instance, the reported tracker already has a finalized cctx; only <= 2 hashes can be submitted for a same pending cctx).

Expected Outcome
Zetaclient should iterate thru all trackers regardless of timeout.