Update discord link to #indexers channel (#505)

* Update discord link

* Add curators link

Author: azf20

website/pages/en/cookbook/upgrading-a-subgraph.mdx

@@ -80,7 +80,7 @@ You should curate your subgraph with GRT to ensure that it is indexed by Indexer
 
 And that's it! After you are done publishing, you'll be able to view your subgraphs live on the decentralized network via [The Graph Explorer](https://thegraph.com/explorer).
 
-Feel free to leverage the [#Curators channel](https://discord.gg/rC8rBuRtbH) on Discord to let Curators know that your subgraph is ready to be signaled. It would also be helpful if you share your expected query volume with them. Therefore, they can estimate how much GRT they should signal on your subgraph.
+Feel free to leverage the [#Curators channel](https://discord.gg/aDrJcJHc) on Discord to let Curators know that your subgraph is ready to be signaled. It would also be helpful if you share your expected query volume with them. Therefore, they can estimate how much GRT they should signal on your subgraph.
 
 ### Create an API key
 
@@ -174,7 +174,7 @@ _While this mechanism is currently live on the network, the community is current
 
 ### Maintaining a Stable Version of a Subgraph
 
-If you're making a lot of changes to your subgraph, it is not a good idea to continually update it and front the update costs. Maintaining a stable and consistent version of your subgraph is critical, not only from the cost perspective but also so that Indexers can feel confident in their syncing times. Indexers should be flagged when you plan for an update so that Indexer syncing times do not get impacted. Feel free to leverage the [#Indexers channel](https://discord.gg/rC8rBuRtbH) on Discord to let Indexers know when you're versioning your subgraphs.
+If you're making a lot of changes to your subgraph, it is not a good idea to continually update it and front the update costs. Maintaining a stable and consistent version of your subgraph is critical, not only from the cost perspective but also so that Indexers can feel confident in their syncing times. Indexers should be flagged when you plan for an update so that Indexer syncing times do not get impacted. Feel free to leverage the [#Indexers channel](https://discord.gg/QJg3GMhh) on Discord to let Indexers know when you're versioning your subgraphs.
 
 Subgraphs are open APIs that external developers are leveraging. Open APIs need to follow strict standards so that they do not break external developers' applications. In The Graph Network, a subgraph developer must consider Indexers and how long it takes them to sync a new subgraph **as well as** other developers who are using their subgraphs.