The `InvalidateDeleteRequests` seems not working when one cascade request is a member of multiple chains

[DickyChant]

When I tried to use the InvalidateDeleteRequests invalidator, it seems that there has some issue:

[2025-04-08 23:06:04,617][WARNING] Sending requests to target environment: https://cms-pdmv-prod.web.cern.ch/mcm/
[2025-04-08 23:06:05,517][WARNING] Root request will be FULL RESET and its output dataset will be invalidated! This is required to delete all its related chained requests.
[2025-04-08 23:06:07,114][ERROR] Unable to process chained requests. After grouping them by the second request, more than one group has been found. This expects only one.
Request groups: dict_keys(['EXO-RunIISpring21UL16FSSIMDRPremix-00002', 'EXO-RunIISummer20UL16SIM-05784'])
Chained requests: ['EXO-chain_RunIISummer20UL16GEN_flowRunIISpring21UL16FSSIMDRPremix_flowRunIISpring21FSUL16MiniAODv2_flowRunIISpring21FSUL16NanoAODv9-00002',
 'EXO-chain_RunIISummer20UL16GEN_flowRunIISummer20UL16FSSIM_flowRunIISummer20UL16DIGIFSPremix_flowRunIISummer20UL16RECO_flowRunIISummer20UL16FSMiniAODv2_flowRunIISummer20UL16FSNanoAODv9-00002']
[2025-04-08 23:06:07,115][ERROR] Unable to process root request (EXO-RunIISummer20UL16GEN-02259): Unable to process chained requests. After grouping them by the second request, more than one group has been found. This expects only one.
Request groups: dict_keys(['EXO-RunIISpring21UL16FSSIMDRPremix-00002', 'EXO-RunIISummer20UL16SIM-05784'])
Chained requests: ['EXO-chain_RunIISummer20UL16GEN_flowRunIISpring21UL16FSSIMDRPremix_flowRunIISpring21FSUL16MiniAODv2_flowRunIISpring21FSUL16NanoAODv9-00002',
 'EXO-chain_RunIISummer20UL16GEN_flowRunIISummer20UL16FSSIM_flowRunIISummer20UL16DIGIFSPremix_flowRunIISummer20UL16RECO_flowRunIISummer20UL16FSMiniAODv2_flowRunIISummer20UL16FSNanoAODv9-00002']
Traceback (most recent call last):
  File "/Users/stqian/Codes/local_mcm/local_mcm/lib/python3.13/site-packages/rest/applications/mcm/invalidate_request.py", line 376, in invalidate_delete_cascade_requests
    self._invalidate_delete_root_request(
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^
        root_prepid=root_prepid,
        ^^^^^^^^^^^^^^^^^^^^^^^^
        remove_root=remove_root,
        ^^^^^^^^^^^^^^^^^^^^^^^^
        remove_chain=remove_chain,
        ^^^^^^^^^^^^^^^^^^^^^^^^^^
    )
    ^
  File "/Users/stqian/Codes/local_mcm/local_mcm/lib/python3.13/site-packages/rest/applications/mcm/invalidate_request.py", line 312, in _invalidate_delete_root_request
    self._invalidate_delete_chain_requests(
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^
        chain_req_data=chain_req, remove_chain=remove_chain
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    )
    ^
  File "/Users/stqian/Codes/local_mcm/local_mcm/lib/python3.13/site-packages/rest/applications/mcm/invalidate_request.py", line 158, in _invalidate_delete_chain_requests
    raise ValueError(msg)
ValueError: Unable to process chained requests. After grouping them by the second request, more than one group has been found. This expects only one.
Request groups: dict_keys(['EXO-RunIISpring21UL16FSSIMDRPremix-00002', 'EXO-RunIISummer20UL16SIM-05784'])
Chained requests: ['EXO-chain_RunIISummer20UL16GEN_flowRunIISpring21UL16FSSIMDRPremix_flowRunIISpring21FSUL16MiniAODv2_flowRunIISpring21FSUL16NanoAODv9-00002',
 'EXO-chain_RunIISummer20UL16GEN_flowRunIISummer20UL16FSSIM_flowRunIISummer20UL16DIGIFSPremix_flowRunIISummer20UL16RECO_flowRunIISummer20UL16FSMiniAODv2_flowRunIISummer20UL16FSNanoAODv9-00002']

To me, it is getting more and more crucial if we think about the fact that we are now producing v14 and v15 nanoaod at the same time, which means more and more DRPremix requests will be shared by two chains and thus become an issue.

I might be able to help out here as this should be of lower priority, and we can always live with the other member functions.