Get Charity Navigator data for existing EINs

Point this script to a PDC instance with a Charity Navigator GraphQL
API key and PDC Keycloak client/secret, and it will get changemakers
from PDC, use (valid) EINs to fetch some data from Charity Navigator
and post the results to ChangemakerFieldValues.

Issue #7 Make a charity navigator data import script

Co-Authored-By: Dan Schultz <slifty@gmail.com>

Author: bickelj

.env.example

@@ -1,6 +1,9 @@
 # Candid Premier API subscription key
 DS_CANDID_API_KEY=my-candid-api-key
 
+# Candid Premier API subscription key
+DS_CHARITY_NAVIGATOR_API_KEY=my-charity-navigator-api-key
+
 # Location of OpenID Connect authority
 DS_OIDC_BASE_URL=https://auth.philanthropydatacommons.org/realms/pdc