[TM-262] Extend set of rules where DIP is redundant

Description

Problem: our optimizer has noDipNeeded rule, but it does not consider some cases where DIP can be erased.

Solution: add two new rules:

• UNIT followed by DIP, it is essentially the same as PUSH followed by DIP.
• DIP followed by DROP.

Related issue(s)

https://issues.serokell.io/issue/TM-262

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