Add basic tests for HTML interface for editing notices

[cryptix]

We should nail down the endpoints and query parameters of them.

The admin test suite for allow-list should give a good idea how this can be done. https://github.com/ssb-ngi-pointer/go-ssb-room/blob/f774817536669c4f2ce2fe356a172d047ef5e780/web/handlers/admin/allow_list_test.go#L109

Check that

• admidb/sqlite: the default notices are present (/notice?id=x for different x's)
• web/handlers: the edit buttons show for logged in admins
• web/handlers/admin: the edit form includes all the needed fields, for input=hidden and input=text
  • for add translation (new)
  • for edit (existing)
• web/handlers/admin: the save handlers refuse incomplete requests (all the params included)
• web/handlers/admin: make sure the save handler calls the mockdb (CallCount and CallArgs)

[cblgh]

preemptively assigning myself to #44 & #46

will see which one i feel i can get more traction on :^)

[cblgh]

@cryptix

the edit form includes all the needed fields, for input=hidden and input=text

Would you mind briefly & explicitly enumerating the needed fields/expected forms? Not really familiar with what's supposed to be included or not atm :)

content
language 
title
id (the only hidden one)

[cblgh]

i'm... done? the onboarding is COMPLETE? hit me up with that review @cryptix lemme know where i have been lacking or misunderstood things