Update README.md (#3253)

Added percentify,  a data analysis toolkit for exploring and profiling datasets quickly.

Author: dmitriy1ikobe

README.md

@@ -493,6 +493,9 @@ _Libraries for data analysis._
 - [modin](https://github.com/modin-project/modin) - A drop-in pandas replacement that scales workflows by changing a single line of code.
 - [pandas](https://github.com/pandas-dev/pandas) - A library providing high-performance, easy-to-use data structures and data analysis tools.
 - [pathway](https://github.com/pathwaycom/pathway) - Real-time data processing framework for Python with reactive dataflows.
+
+- [percentify](https://github.com/data-centt/percentify) - Exploratory stats and data-quality diagnostics/profiler, that supports both pandas and Polars DataFrames inputs.
+
 - [polars](https://github.com/pola-rs/polars) - A fast DataFrame library implemented in Rust with a Python API.
 
 ### Data Ingestion / ETL