Adding link to pricing page (#917)

Author: MichaelMacaulay

Diff for: website/src/pages/en/subgraphs/billing.mdx

@@ -10,6 +10,8 @@ There are two plans to use when querying Subgraphs on The Graph Network.
 
 - **Growth Plan**: The Growth Plan includes everything in the Free Plan with all queries after 100,000 monthly queries requiring payments with GRT or credit card. The Growth Plan is flexible enough to cover teams that have established dapps across a variety of use cases.
 
+Learn more about pricing [here](https://thegraph.com/studio-pricing/).
+
 <VideoEmbed title="How to Set Up Billing on The Graph Network" youtube="Nn771WagX2I" />
 
 ## Query Payments with credit card