Fixes for Clang warnings

[HennerM]

I was trying to compile triton server with default Clang 15 and got a few warnings that triggered as errors, among those:

• deprecation errors from open telemetry showing up, which shouldn't be an issue here. They come up because the headers aren't included as "SYSTEM" headers.
• unused parameter in TritonParser::SetGlobalTraceArgs(). There is a explicit_disable_trace passed as bool, that was updated but never read. I believe this was intended to be a bool& @oandreeva-nv ? (error: parameter 'explicit_disable_trace' set but not used [-Werror,-Wunused-but-set-parameter])
• An unused [this] capture (-Wunused-lambda-capture)
• Assignment with std::move of temporary variable resulting in: error: moving a temporary object prevents copy elision [-Werror,-Wpessimizing-move] I am not quite sure what's the problem, but I think the std::move is redundant here anyway?
• a few conditionally uninitialised variables in tests variable 'ba_memory_type' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized]
• unused private field in HTTPAPIServer: error: private field 'end_' is not used [-Werror,-Wunused-private-field] bool end_{false};

There is more in the core and backend repos that I will raise separately

[rmccorm4]

Hi @HennerM, thanks for the contributions, these look great! Can you update the branch and resolve the conflicts? Then we can run some quick tests to make sure nothing breaks and approve.

[rmccorm4]

~~Also just to double check, have you sent in a CLA as described here: https://github.com/triton-inference-server/server/blob/main/CONTRIBUTING.md#contributor-license-agreement-cla?~~ Nevermind, I see one already filled out for you and Speechmatics.