VcsBase: Get rid of CommandOutputBindMode

Simplify createCommand() implementation. All callers
passed either non-null editor (in this case the
bindMode was always NoBind) or passed a null editor and one
of two values for bindMode (in this case the only
effect was to add (or not) a RunFlags::ShowStdOut flag).

Drop CommandOutputBindMode enum completely and pass
directly RunFlags::ShowStdOut when needed (i.e. in cases
we were passing CommandOutputBindMode::ToVcsWindow).

Change-Id: Ic3af05818933a03f615ba02267403b9f0bd326ba
Reviewed-by: Orgad Shaneh <orgads@gmail.com>

src/plugins/git/gitplugin.cpp

@@ -1584,7 +1584,7 @@ void GitPluginPrivate::instantBlame()
     };
     GitClient::instance()->vcsExecWithHandler(workingDirectory,
                            {"blame", "-p", "-L", lineString, "--", filePath.toString()},
-                           this, commandHandler, RunFlags::NoOutput, CommandOutputBindMode::NoBind);
+                           this, commandHandler);
 }
 
 void GitPluginPrivate::stopInstantBlame()