v5.0 compile error

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Please ensure that your bug report is clear and that it is complete. Otherwise, we may be unable to understand it or to reproduce it, either of which would prevent us from fixing the bug. We strongly recommend the report(bug report or feature request) could include some hints as to the following:

**BUG REPORT**

1. Please describe the issue you observed:
use clang 17.0.1 compile , cmake

```
src/main/cpp/base/include/HttpClientImpl.h:42:78: error: expected ';' at end of declaration list
42 | absl::flat_hash_map> clients_ GUARDED_BY(clients_mtx_);

```

- What did you do (The steps to reproduce)?

- What did you expect to see?

- What did you see instead?

2. Please tell us about your environment:
rock linx
compiler clang 17.0.1
client v5.0-rc2

Start with src/main/cpp/base/include/HttpClientImpl.h at line 42 and reproduce the CMake build using Clang 17.0.1 on the reported Rock Linux environment. Confirm the cause of the declaration error and verify that the v5.0-rc2 client compiles successfully afterward.

Scritto dal modello di indicizzazione a partire dal testo della issue.