bitbake: command: Ensure exceptions inheriting from BBHandledException are visible

Previous changes allowed BBHandledException to be detected but not exceptions
which inherit from it. Fix this. The code really needs totally reworking
to preserve the exceptions.

[YOCTO #14054]

(Bitbake rev: ef762d92df6c2554c6248e80212f984d9ec4c651)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bb/command.py

@@ -81,8 +81,12 @@ class Command:
                 result = command_method(self, commandline)
             except CommandError as exc:
                 return None, exc.args[0]
-            except (Exception, SystemExit):
+            except (Exception, SystemExit) as exc:
                 import traceback
+                if isinstance(exc, bb.BBHandledException):
+                    # We need to start returning real exceptions here. Until we do, we can't
+                    # tell if an exception is an instance of bb.BBHandledException
+                    return None, "bb.BBHandledException()\n" + traceback.format_exc()
                 return None, traceback.format_exc()
             else:
                 return result, None