During the rolling upgrade from 2.5 to 2.6, the 2.5 coordinator detects
newly started 2.6 proxies. However, 2.6 proxies do not sync timetick,
which leads to timetick delay. This PR ignores 2.6 proxies to prevent
ttDelay during the upgrade process.
issue: https://github.com/milvus-io/milvus/issues/43518
Signed-off-by: bigsheeper <yihao.dai@zilliz.com>
issue: #28898
This PR move the `ProxyClientManager` to util package, in case of
reusing it's implementation in querycoord
Signed-off-by: Wei Liu <wei.liu@zilliz.com>