Add support for virtual invokes on enums

[CaelmBleidd]

Description

Now we create enum instances without concrete type when it comes as a parameter into a function. This allows us to support virtual invokes on enum instances.

Also, this request contains some a fix related to resolving enum instances retrieved from concrete and its instantiation in the Resolver: we should use everywhere not a type for some enum constant, but a type of its superclass (since an enum constant is not an enum in accordance to java.lang.Class#isEnum). Corresponding comments are added to the code.

Fixes JIRA:1686, JIRA:1450

How to test

Automated tests

Tests from class org.utbot.examples.enums.ClassWithEnumTest

Manual tests

There are no manual tests.

Self-check list

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