issue: https://github.com/milvus-io/milvus/issues/38877
1. refactor pymilvus client v2 testcasebase
2. add a test for search hint
3. update pymilvus to 2.6
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Signed-off-by: yanliang567 <yanliang.qiao@zilliz.com>
related issue: https://github.com/milvus-io/milvus/issues/32653
1. align some default index params
2. add a new range search tests for all indexes and float vectors
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Signed-off-by: yanliang567 <yanliang.qiao@zilliz.com>