Use DataSetPtr in all knowhere interfaces

[cydrain]

To support multi data type, PR #210 introduced IndexNodeDataMockWrapper::xxx, in which DataSet reference is converted into shared_ptr.
This operation has panic risk, because if the DataSet is not created by make_shared, but created in stack,
calling shared_from_this will cause bad_weakptr.
To avoid this kind of risk, need change all DataSet& to DataSetPtr in all knowhere APIs.

For details please check #210 and #659

[alexanderguzhva]

I would personally stick with std::shared_ptr<DataSet> instead of creating an alias 'DataSetPtr'. Just because it is confusing (DataSetPtr kinda implies DataSet*)
Also, const std::shared_ptr<DataSet> should be passed by ref, because passing shared_ptr by value adds an overhead of atomic increments and decrements of shared_ptr ref counters.

So, not

    virtual expected<DataSetPtr>
    Search(const DataSetPtr dataset, const Config& cfg, const BitsetView& bitset) const = 0;

but

    virtual expected<std::shared_ptr<DataSet>>
    Search(const std::shared_ptr<DataSet>& dataset, const Config& cfg, const BitsetView& bitset) const = 0;

[github-actions]

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