fix(p2p): enable auto join when online (#5738)

Description
---
Enable auto network join by default

Motivation and Context
---
At some point auto_join was set to false for base node and wallet.

How Has This Been Tested?
---
Manually - nodes detect a node coming online from the join message

What process can a PR reviewer use to test or verify this change?
---

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Breaking Changes
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- [x] None
- [ ] Requires data directory on base node to be deleted
- [ ] Requires hard fork
- [ ] Other - Please specify

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base_layer/p2p/src/config.rs

@@ -141,6 +141,7 @@ impl Default for P2pConfig {
             max_concurrent_outbound_tasks: 4,
             dht: DhtConfig {
                 database_url: DbConnectionUrl::file("dht.sqlite"),
+                auto_join: true,
                 ..Default::default()
             },
             allow_test_addresses: false,