[SHT_LLVM_BB_ADDR_MAP,NFC] Add SCOPED_TRACE for convenient mapping of failures to test cases.

[rlavaee]

Although parameterized gtests are preferred for this, our tests are not very straightforward. So I decided to add SCOPED_TRACE for different test cases and the lambda checks as well.

Typical test failure message now looks like:

...llvm-project/llvm/unittests/Object/ELFObjectFileTest.cpp:737
Expected equality of these values:
  *BBAddrMaps
    Which is: { 32-byte object <11-11 01-00 00-00 00-00 C0-A9 FB-3E E4-55 00-00 D0-A9 FB-3E E4-55 00-00 D0-A9 FB-3E E4-55 00-00>, 32-byte object <22-22 02-00 00-00 00-00 F0-8E FB-3E E4-55 00-00 00-8F FB-3E E4-55 00-00 00-8F FB-3E E4-55 00-00> }
  ExpectedResult
    Which is: { 32-byte object <33-33 03-00 00-00 00-00 50-A7 FB-3E E4-55 00-00 60-A7 FB-3E E4-55 00-00 60-A7 FB-3E E4-55 00-00> }
Google Test trace:
...llvm-project/llvm/unittests/Object/ELFObjectFileTest.cpp:726: for TextSectionIndex: 1 and object yaml:

--- !ELF
FileHeader:
  Class: ELFCLASS64
  Data:  ELFDATA2LSB
  Type:  ET_EXEC
Sections:
  - Name: .llvm_bb_addr_map_1
    Type: SHT_LLVM_BB_ADDR_MAP
    Link: 1
    Entries:
      - Version: 2
        Address: 0x11111
        BBEntries:
          - ID:            1
            AddressOffset: 0x0
            Size:          0x1
            Metadata:      0x2
  - Name: .llvm_bb_addr_map_2
    Type: SHT_LLVM_BB_ADDR_MAP
    Link: 1
    Entries:
      - Version: 2
        Address: 0x22222
        BBEntries:
          - ID:            2
            AddressOffset: 0x0
            Size:          0x2
            Metadata:      0x4
  - Name: .llvm_bb_addr_map_3
    Type: SHT_LLVM_BB_ADDR_MAP
    Link: 2
    Entries:
      - Version: 1
        Address: 0x33333
        BBEntries:
          - ID:            0
            AddressOffset: 0x0
            Size:          0x3
            Metadata:      0x6
  - Name: .llvm_bb_addr_map_4
    Type: SHT_LLVM_BB_ADDR_MAP_V0
  # Link: 0 (by default, can be overriden)
    Entries:
      - Version: 0
        Address: 0x44444
        BBEntries:
          - ID:            0
            AddressOffset: 0x0
            Size:          0x4
            Metadata:      0x18

...llvm-project/llvm/unittests/Object/ELFObjectFileTest.cpp:757: normal sections

[red1bluelost]

LGTM, extra context seems helpful.