Rename Interfaces class as the Base class

[nocotan]

Summary

To clarify the role of class, we should rename the class as follows:

InterfaceTimeSeriesMetrics -> BaseTimeSeriesMetrics

This issue will be assigned after all implementations of the interface class are finished.

Goal

Refactor all corresponding codes.

Todo

• [x] rename class name
• [x] rewrite the code which is using the interface class
• [x] check if all unit tests are passed

Deadline

yyyy / mm / dd

Parent issue

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References

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Notes

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