[clang] [clang-tools-extra] [compiler-rt] [Clang] [NFC] Fix more `-Wreturn-type` warnings in tests everywhere (PR #123470)

[LLVM Continuous Integration via cfe-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `llvm-clang-x86_64-sie-ubuntu-fast` running on `sie-linux-worker` while building `clang-tools-extra,clang,compiler-rt` at step 6 "test-build-unified-tree-check-all".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/144/builds/18525

<details>
<summary>Here is the relevant piece of the build log for the reference</summary>

```
Step 6 (test-build-unified-tree-check-all) failure: test (failure)
******************** TEST 'Clang Tools :: clang-tidy/checkers/readability/named-parameter.cpp' FAILED ********************
Exit Code: 1

Command Output (stdout):
--
Running ['clang-tidy', '/home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/tools/clang/tools/extra/test/clang-tidy/checkers/readability/Output/named-parameter.cpp.tmp.cpp', '-fix', '--checks=-*,readability-named-parameter', '--config={}', '--', '-std=c++11', '-nostdinc++']...
clang-tidy /home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/tools/clang/tools/extra/test/clang-tidy/checkers/readability/Output/named-parameter.cpp.tmp.cpp -fix --checks=-*,readability-named-parameter --config={} -- -std=c++11 -nostdinc++ failed:
18 warnings and 2 errors generated.
Error while processing /home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/tools/clang/tools/extra/test/clang-tidy/checkers/readability/Output/named-parameter.cpp.tmp.cpp.
/home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/tools/clang/tools/extra/test/clang-tidy/checkers/readability/Output/named-parameter.cpp.tmp.cpp:3:19: warning: all parameters should be named in a function [readability-named-parameter]
    3 | void Method(char *) { /* */ }
      |                   ^
      |                    /*unused*/
/home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/tools/clang/tools/extra/test/clang-tidy/checkers/readability/Output/named-parameter.cpp.tmp.cpp:6:20: warning: all parameters should be named in a function [readability-named-parameter]
    6 | void Method2(char *) {}
      |                    ^
      |                     /*unused*/
/home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/tools/clang/tools/extra/test/clang-tidy/checkers/readability/Output/named-parameter.cpp.tmp.cpp:9:20: warning: all parameters should be named in a function [readability-named-parameter]
    9 | void Method3(char *, void *) {}
      |                    ^       
      |                     /*unused*/  /*unused*/
/home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/tools/clang/tools/extra/test/clang-tidy/checkers/readability/Output/named-parameter.cpp.tmp.cpp:12:20: warning: all parameters should be named in a function [readability-named-parameter]
   12 | void Method4(char *, int /*unused*/) {}
      |                    ^
      |                     /*unused*/
/home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/tools/clang/tools/extra/test/clang-tidy/checkers/readability/Output/named-parameter.cpp.tmp.cpp:15:30: warning: all parameters should be named in a function [readability-named-parameter]
   15 | void operator delete[](void *) throw() {}
      |                              ^
      |                               /*unused*/
/home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/tools/clang/tools/extra/test/clang-tidy/checkers/readability/Output/named-parameter.cpp.tmp.cpp:18:16: warning: all parameters should be named in a function [readability-named-parameter]
   18 | int Method5(int) { return 0; }
      |                ^
      |                 /*unused*/
/home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/tools/clang/tools/extra/test/clang-tidy/checkers/readability/Output/named-parameter.cpp.tmp.cpp:21:21: warning: all parameters should be named in a function [readability-named-parameter]
   21 | void Method6(void (*)(void *)) {}
      |                     ^
      |                      /*unused*/
/home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/tools/clang/tools/extra/test/clang-tidy/checkers/readability/Output/named-parameter.cpp.tmp.cpp:24:37: warning: all parameters should be named in a function [readability-named-parameter]
   24 | template <typename T> void Method7(T) {}
      |                                     ^
      |                                      /*unused*/
/home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/tools/clang/tools/extra/test/clang-tidy/checkers/readability/Output/named-parameter.cpp.tmp.cpp:40:23: error: cannot use 'throw' with exceptions disabled [clang-diagnostic-error]
   40 |   X operator++(int) { throw 0; }
      |                       ^
/home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/tools/clang/tools/extra/test/clang-tidy/checkers/readability/Output/named-parameter.cpp.tmp.cpp:41:23: error: cannot use 'throw' with exceptions disabled [clang-diagnostic-error]
   41 |   X operator--(int) { throw 0; }
      |                       ^
/home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/tools/clang/tools/extra/test/clang-tidy/checkers/readability/Output/named-parameter.cpp.tmp.cpp:55:13: warning: all parameters should be named in a function [readability-named-parameter]
   55 |   void foo(T) {}
      |             ^
...

```

</details>

https://github.com/llvm/llvm-project/pull/123470