IGNITE-22964 Java thin: fix client init hang on unreachable discovered address

[ptupitsyn]

• Do not perform cluster discovery synchronously while initializing the client - do applyOnDefaultChannel before checking channelsCnt.get() == 0 in channelsInit
• Do not disconnect active channels when performing discovery, even if those addresses are not in the new list to avoid unnecessary reconnects

[sonarcloud[bot]]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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