Fetch delegate based on public key or wallet address

[roks0n]

Allow fetching a delegate based on public key and wallet address.

[roks0n]

Looks like fetching by wallet address was "implemented" but is broken:

arkdelegates/src/app/views/api/urls.py

Lines 12 to 16 in cf07cce

	re_path(
	r"delegates/(?P<wallet_address>[0-9A-Za-z]{34})/$",
	Delegates.as_view(),
	name="api-delegate-a",
	),