Intent of TestTruncateUTF8

All 2 exact tests in this concept. Every test is marked by where it enters the hierarchy.

go.temporal.io/ 2 tests
- server/ 2 tests
  - common/ 2 tests
    
    failure/ 1 test
    
    go.temporal.io/server/common/failure/TestTruncateUTF8 Inherited TestTruncateUTF8
    
    util/ 1 test
    
    go.temporal.io/server/common/util/TestTruncateUTF8 Introduced here