Support union types normalization · Pull Request !1496 · OpenHarmony/arkcompiler_ets_frontend

### Issue: 
https://gitee.com/openharmony/arkcompiler_ets_frontend/issues/I8NVZM?from=project-issue
### Reason (target, resolving problems, etc): 
Need to implement union types normalization from 3.8.11 spec.
### Description: 
Rules from the spec 3.8.11:
1. All nested union types are linearized.
2. Identical types within the union type are replaced for a single type.
3. Identical literals within the union type are replaced for a single literal.
4. If at least one type in the union is Object, then the entire union type is reduced to Object type.
5. If there is type never among union types, then it is removed.
6. If there is a number type among numeric union types or numeric literals, then all such types or literals are
replaced for type number.
7. If a literal of union type belongs to the values of a type that is part of the union, then the literal is removed.
8. This step is performed recursively until no mutually compatible types remain (see Compatible Types), or the union type is reduced to a single type:
 - If a union type includes two types Ti and Tj (i != j), and Ti is compatible with Tj (see Compatible Types), then only Tj remains in the union type, and Ti is removed.
 - If Tj is compatible with Ti (see Compatible Types), then Ti remains in the union type, and Tj is removed.
 
### Test scenarios (new, modified, affected functions):
es2panda, ark, verifier in test-u-runner

Change-Id: I2a7e72f83afae14e25014ceaac0364613443edf2

类型	指派人员	状态
审查	@egavrin 由 CODEOWNERS 文件第 15 行指派为审查者	进行中 (0/1人)
审查	godmiaozi zhuoli72 徐城	进行中 (0/1人)
测试	openharmony_ci	进行中 (0/1人)

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