Revert "[lldb][test] Add test-coverage for DW_AT_APPLE_objc_complete_type parsing (#120279)"

This reverts commit 000febd.

This is failing on the macOS public buildbots. It's unclear
to me why (I can't reproduce the failure on my local M1 machine).
I suspect the test might be relying on some non-deterministic
linker properties (such as order of entries in the debug-map
or something like that). The failure is as follows:
```
CHECK-NEXT: expected string not found in input
              ^
<stdin>:25:7: note: scanning from here
 y = 2
      ^
<stdin>:27:4: note: possible intended match here
(lldb) exit
   ^

Input file: <stdin>
Check file: /Users/ec2-user/jenkins/workspace/llvm.org/as-lldb-cmake/llvm-project/lldb/test/Shell/Expr/TestObjCHiddenIvars.test

-dump-input=help explains the following input dump.

Input was:
<<<<<<
           .
           .
           .
          20: (lldb) expression *f
          21: (Foo) $0 = {
          22:  NSObject = {
          23:  isa = Foo
          24:  }
          25:  y = 2
next:21'0           X error: no match found
          26: }
next:21'0     ~~
          27: (lldb) exit
next:21'0     ~~~~~~~~~~~~
next:21'1        ?         possible intended match
>>>>>>
```

Author: Michael137