readme: update discord links (#6965)

This updates the Discord invite links.

docs/.vuepress/config.js

@@ -78,7 +78,7 @@ module.exports = {
     },
     footer: {
       question: {
-        text: 'Chat with Tendermint developers in <a href=\'https://discord.gg/vcExX9T\' target=\'_blank\'>Discord</a> or reach out on the <a href=\'https://forum.cosmos.network/c/tendermint\' target=\'_blank\'>Tendermint Forum</a> to learn more.'
+        text: 'Chat with Tendermint developers in <a href=\'https://discord.gg/cosmosnetwork\' target=\'_blank\'>Discord</a> or reach out on the <a href=\'https://forum.cosmos.network/c/tendermint\' target=\'_blank\'>Tendermint Forum</a> to learn more.'
       },
       logo: '/logo-bw.svg',
       textLink: {

docs/tools/debugging/pro.md

@@ -99,7 +99,7 @@ We’re hoping that these Tendermint tools will become de facto the first respon
 
 Let us know what your experience has been so far! Have you had a chance to try `tendermint debug` or `tendermint inspect` yet?
 
-Join our [discord chat](https://discord.gg/vcExX9T), where we discuss the current issues and future improvements.
+Join our [discord chat](https://discord.gg/cosmosnetwork), where we discuss the current issues and future improvements.
 
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