Automatic update for grpc-1.26.0-13.eln110.

Changelog

* Tue Mar 23 2021 Benjamin A. Beasley <code@musicinmybrain.net> - 1.26.0-13
- General:
  * Replace * with • in descriptions
  * Use cmake() dependencies first, and pkgconfig() dependencies second, where
    available
  * Drop explicit pkgconfig BR
  * Fix the directory in which CMake installs pkgconfig files
  * Improved CMake options
  * Build the Doxygen reference manuals
- C (core) and C++ (cpp):
  * Let the -devel package require cmake-filesystem
  * Allow building tests with our own copy of gtest/gmock, which will become
    mandatory when we depend on abseil-cpp and switch to C++17
  * Fix a link error in the core tests when using CMake
  * Manually install grpc_cli (CMake)
  * Add CMake files to the files list for the -devel package
  * Start running some of the core tests in %check
- Python:
  * Add several patches required for the tests
  * BR gevent for gevent_tests
  * Fix build; in particular, add missing preprocess and build_package_protos
    steps, without which the packages were missing generated proto modules and
    were not
    usable!
  * Add %py_provides for Fedora 32
  * Drop python3dist(setuptools) BR, redundant with %pyproject_buildrequires
  * Start running most of the Python tests in %check
  * Merge the python-grpcio-doc subpackage into grpc-doc