* upgrade ruby docker images to debian 11
* upgrade C# docker images to debian11
* update sanity dockerimage to debian11
* upgrade cxx interop to debian11
* add ccache to python interop images
* enable use of ccache for interop tests
* adjust run_tests.py to new docker images
* add ccache to rake-compiler-dock docker images
* improve prepare_ccache_symlinks_rc
* enable use of ccache in rake-compiler-dock docker containers
* add ccache support for python_manylinux2014_aarch64
* add ccache support for python_linux_armv7
* deduplicate python3.9 install
* ccache for crosscompiled darwin gems is broken
* fix bash -l resetting of PATH in grpc_artifact_python_linux_armv7
six is necessary for making these scripts cross compatible
between python 2.x and 3.x
Changes:
Add six to python_deps.include
Include python_deps.include to all Dockerfile templates in test directory
Include python_deps.include to all Dockerfile templates in stress_test directory
Include python_deps.include to all Dockerfile templates in interop_test directory
Replace print statements with print function calls (from futute..)
Replace .iteritems() with .items() wherever necessary
use six.moves to import BaseHTTPServer
Generate new dockerfiles using generate_projects.sh