Add admin & member endpoints for updating/deleting entities

[eleftherioszisis]

Update (22 Aug):
To include members also now, as per comments here

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In order to be able to manipulate/maintain entities, admin endpoints are needed for now to allow updating/deleting entities.

Deletion Proposal
https://openbraininstitute-my.sharepoint.com/:w:/g/personal/eleftherios_zisis_openbraininstitute_org/ESvrs0SCTHhMsyQUpGr39zoBqf4hhCwLMU1skONlTb3cuw?e=UJ0S9d

Update Proposal
https://openbraininstitute-my.sharepoint.com/:w:/g/personal/eleftherios_zisis_openbraininstitute_org/Edx8zcDDk7pDnUvuAytASXIBDN36oek-7qw8iB31PfYIkw?e=O5wCgt

• Update endpoints for users Add update endpoints for users #347
• Update endpoints for service admins Add update endpoints for service admins #355
• Delete endpoints for users Add delete endpoints for users #379
• Delete endpoints for service admins. Add admin delete endpoints for all routers #281

[evakennyobi]

updating to do also still

[evakennyobi]

deletion proposal to be drafted

[evakennyobi]

proposal ready today

[eleftherioszisis]

I updated #281 with the admin deletion endpoints to allow deletion with limited cascades for associations (e.g. contributions, classifications) when an entity is deleted, but assets must be explicitly deleted before an entity can be deleted.

[evakennyobi]

if private, then a user could have the option to delete, but with notification
if public, only OBI can delete

for deletions would need to also delete the entry

user endpoints comes after, separate to this pr

who can delete? admin, user can delete what they have access to?
above requires further discussion