[TM-379] Go into deep lambdas in dfsInstr

Description

Problem: dfsInstr has a flag that specifies whether it should be applied to instructions inside lambdas. When this flag is enabled, it applies recursion to PUSH lambda case. But it treats all other PUSHes as if they didn't contain any instructions. However, there can be values of a type different from lambda that contain instructions, e. g. pair a (lambda b c). Currently instructions in such values are ignored.

Solution: apply dfsValue when we encounter PUSH regardless of the type of the pushed value. This dfsValue's step recursively calls our dfsInstr. The test added in this commit confirms there was this problem.

Related issue(s)

https://issues.serokell.io/issue/TM-379

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