chore: provide a CLI flag to open log.html

On macOS, this was done by default regardless of what the user wants.
This was also not done on Windows or Linux. Instead, we now provide a
`--open-log` flag to open the log file in the default browser, and it
works on all platforms.

cli/src/tests/corpus_test.rs

@@ -544,7 +544,7 @@ fn get_parser(session: &mut Option<util::LogSession>, log_filename: &str) -> Par
             }
         })));
     } else if *LOG_GRAPH_ENABLED {
-        *session = Some(util::log_graphs(&mut parser, log_filename).unwrap());
+        *session = Some(util::log_graphs(&mut parser, log_filename, false).unwrap());
     }
 
     parser