Merge bitcoin#28989: test: Fix test by checking the actual exception …

…instance

55e3dc3 test: Fix test by checking the actual exception instance (Hennadii Stepanov)

Pull request description:

  The `system_tests/run_command` test is broken because it passes even with the diff as follows:
  ```diff
  --- a/src/test/system_tests.cpp
  +++ b/src/test/system_tests.cpp
  @@ -90,7 +90,7 @@ BOOST_AUTO_TEST_CASE(run_command)
           });
       }
       {
  -        BOOST_REQUIRE_THROW(RunCommandParseJSON("echo \"{\""), std::runtime_error); // Unable to parse JSON
  +        BOOST_REQUIRE_THROW(RunCommandParseJSON("invalid_command \"{\""), std::runtime_error); // Unable to parse JSON
       }
       // Test std::in, except for Windows
   #ifndef WIN32
  ```

  The reason of such fragility is that the [`BOOST_REQUIRE_THROW`](https://www.boost.org/doc/libs/1_83_0/libs/test/doc/html/boost_test/utf_reference/testing_tool_ref/assertion_boost_level_throw.html) macro passes even if the command raises an exception in the underlying subprocess implementation, which might have a type derived from `std::runtime_error`.

ACKs for top commit:
  maflcko:
    lgtm ACK 55e3dc3
  achow101:
    ACK 55e3dc3
  furszy:
    Non-Windows code ACK 55e3dc3
  pablomartin4btc:
    ACK 55e3dc3

Tree-SHA512: 32f49421bdcc94744c81e82dc10cfa02e3f8ed111974edf1c2a47bdaeb56d7baec1bede67301cc89464fba613029ecb131dedc6bc5948777ab52f0f12df8bfe9

src/test/system_tests.cpp

@@ -77,7 +77,13 @@ BOOST_AUTO_TEST_CASE(run_command)
         });
     }
     {
-        BOOST_REQUIRE_THROW(RunCommandParseJSON("echo \"{\""), std::runtime_error); // Unable to parse JSON
+        // Unable to parse JSON
+#ifdef WIN32
+        const std::string command{"cmd.exe /c echo {"};
+#else
+        const std::string command{"echo {"};
+#endif
+        BOOST_CHECK_EXCEPTION(RunCommandParseJSON(command), std::runtime_error, HasReason("Unable to parse JSON: {"));
     }
     // Test std::in, except for Windows
 #ifndef WIN32