feat: simple discover all command

shows which tests are executed without running them.

Author: d-biehl

Diff for: packages/runner/src/robotcode/runner/cli/discover/discover.py

@@ -232,7 +232,7 @@ def print(item: TestItem, indent: int = 0) -> Iterable[str]:
                     for child in item.children:
                         yield from print(child, indent + 2)
 
-            click.echo_via_pager(print(collector.result))
+            app.echo_via_pager(print(collector.result))
         else:
             app.print_data(collector.result, remove_defaults=True)
     except DataError as err: