When stamping a group that shares a link error, this causes all links to contain the same stamping.
This fix allows each errback to have its own stamps by using `clone()` when linking the errback signature.

This fix also takes into consideration Chords with the [allow_error_cb_on_chord_header](https://docs.celeryq.dev/en/stable/userguide/configuration.html#task-allow-error-cb-on-chord-header) flag True.
Stamping bugfix with group/chord header errback linking. When stamping a group that shares a link error, this causes all links to contain the same stamping.
This fix allows each errback to have its own stamps by using `clone()` when linking the errback signature.

This fix also takes into consideration Chords with the [allow_error_cb_on_chord_header](https://docs.celeryq.dev/en/stable/userguide/configuration.html#task-allow-error-cb-on-chord-header) flag True.