docs: Metrics update (bp #13239) (#13241)

* docs: Remove stale metrics steps

(cherry picked from commit 4dc4fefee2)

* docs: Reference metrics envvars for each cluster

(cherry picked from commit eb597cd60f)

Co-authored-by: Trent Nelson <trent@solana.com>

docs/src/clusters.md

@@ -24,6 +24,10 @@ Explorers:
   - Devnet may be subject to ledger resets
   - Devnet typically runs a newer software version than Mainnet Beta
 - Gossip entrypoint for Devnet: `entrypoint.devnet.solana.com:8001`
+- Metrics environment variable for Devnet:
+```bash
+export SOLANA_METRICS_CONFIG="host=https://metrics.solana.com:8086,db=devnet,u=scratch_writer,p=topsecret"
+```
 - RPC URL for Devnet: `https://devnet.solana.com`
 
 ##### Example `solana` command-line configuration
@@ -65,6 +69,10 @@ The `--trusted-validator`s is operated by Solana
 - Testnet typically runs a newer software release than both Devnet and
   Mainnet Beta
 - Gossip entrypoint for Testnet: `entrypoint.testnet.solana.com:8001`
+- Metrics environment variable for Testnet:
+```bash
+export SOLANA_METRICS_CONFIG="host=https://metrics.solana.com:8086,db=tds,u=testnet_write,p=c4fa841aa918bf8274e3e2a44d77568d9861b3ea"
+```
 - RPC URL for Testnet: `https://testnet.solana.com`
 
 ##### Example `solana` command-line configuration
@@ -112,6 +120,10 @@ Currently smart contracts, rewards, and inflation are disabled.
     [Trust Wallet](wallet-guide/trust-wallet.md),
     the wallet will always be connecting to Mainnet Beta.
 - Gossip entrypoint for Mainnet Beta: `mainnet-beta.solana.com:8001`
+- Metrics environment variable for Mainnet Beta:
+```bash
+export SOLANA_METRICS_CONFIG="host=https://metrics.solana.com:8086,db=mainnet-beta,u=mainnet-beta_write,p=password"
+```
 - RPC URL for Mainnet Beta: `https://api.mainnet-beta.solana.com`
 
 ##### Example `solana` command-line configuration

docs/src/running-validator/validator-monitor.md

@@ -46,25 +46,6 @@ curl -X POST -H "Content-Type: application/json" -d '{"jsonrpc":"2.0","id":1, "m
 curl -X POST -H "Content-Type: application/json" -d '{"jsonrpc":"2.0","id":1, "method":"getEpochInfo"}' http://devnet.solana.com
 ```
 
-## Validator Metrics
-
-Metrics are available for local monitoring of your validator.
-
-Docker must be installed and the current user added to the docker group. Then
-download `solana-metrics.tar.bz2` from the Github Release and run
-
-```bash
-tar jxf solana-metrics.tar.bz2
-cd solana-metrics/
-./start.sh
-```
-
-A local InfluxDB and Grafana instance is now running on your machine. Define
-`SOLANA_METRICS_CONFIG` in your environment as described at the end of the
-`start.sh` output and restart your validator.
-
-Metrics should now be streaming and visible from your local Grafana dashboard.
-
 ## Timezone For Log Messages
 
 Log messages emitted by your validator include a timestamp. When sharing logs