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>
1. modify test case: test_search_repeatedly_ivf_index_different_limit
2. update pymilvus version from 2.4.0rc19 to 2.4.0rc24
3. Before, insert will return a pk list. In the latest milvus client,
insert will return a number that is inserted successfully
4. In the latest milvus client, flush and num_entities have been removed
5. Before, the default consistency level of a new collection is strong.
In the latest milvus client, it becomes bounded. So related cases have
been modified correspondingly, or immediate search after insert will
return no results.
6. In the latest pymilvus, new data type FLOAT16_VECTOR and
BFLOAT16_VECTOR have been added.
Signed-off-by: nico <cheng.yuan@zilliz.com>
