fix: make proof data handler backwards compatible (#3767)

## What ❔

Revert WS-related changes for proof data handler

## Why ❔

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## Is this a breaking change?
- [ ] Yes
- [ ] No

## Operational changes
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## Checklist

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- [ ] PR title corresponds to the body of PR (we generate changelog
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- [ ] Tests for the changes have been added / updated.
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lint`.

Author: Artemka374

crates/zkstack/src/commands/chain/init/configs.rs

@@ -68,13 +68,6 @@ pub async fn init_configs(
         general_config.insert("prover_gateway.api_url", format!("http://127.0.0.1:{port}"))?;
     }
 
-    let prover_gateway_port = general_config
-        .base()
-        .get_opt::<u16>("prover_gateway.ws_port")?;
-    if let Some(port) = prover_gateway_port {
-        general_config.insert("data_handler.api_url", format!("ws://127.0.0.1:{port}"))?;
-    }
-
     let consensus_keys = generate_consensus_keys();
     set_genesis_specs(&mut general_config, chain_config, &consensus_keys)?;