Update .env.example

Makes it more clear for new users that are setting up Telescope

Author: LeonMontealegre

.env.example

@@ -1,10 +1,12 @@
+# Note that these secrets are completely arbitrary and can be whatever you want for development purposes.
+
 # Used by Hasura
-DATABASE_URL=postgres://USERNAME:EXAMPLE_POSTGRES_PASSWORD@localhost/postgres?sslmode=disable
+DATABASE_URL=postgres://postgres:EXAMPLE_POSTGRES_PASSWORD@db/postgres?sslmode=disable
 
 # The JWT secret used with Hasura.
 RCOS_JWT_SECRET=xxxxxxxxxxxxxxxxxxxxxxxx
-# The admin secret used with Hasura.
-HASURA_GRAPHQL_ADMIN_SECRET=xxxxxxxxxxxxxxxxxxxxxxxx
+# The admin secret used with Hasura, MUST BE AT LEAST 32 characters long!
+HASURA_GRAPHQL_ADMIN_SECRET=xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
 
 # Used by postgres docker. Replace in your version. Should match the password above.
 POSTGRES_PASSWORD=EXAMPLE_POSTGRES_PASSWORD