- require pandas

- update to 2.6.2:
* This release is the result of 11 months of work with over 363 pull requests by
91 contributors. Highlights include:
* Dropped support for Python 3.6.
* NumPy, SciPy, Matplotlib, and pandas are now default requirements.
* NetworkX no longer depends on the library "decorator".
* Improved example gallery
* Removed code for supporting Jython/IronPython
* The __str__ method for graph objects is more informative and concise.
* Improved import time
* Improved test coverage
* New documentation theme
* Add functionality for drawing self-loop edges
* Add approximation algorithms for Traveling Salesman Problem
- drop 0001-Replace-hash-function-for-test-of-weighted-astar.patch,
yaml-loader.patch (merged upstream)