Update to clang-14 and c++20. (#99)

Author: shuoyang2016

.bazelrc

@@ -16,11 +16,11 @@
 # https://github.com/bazelbuild/rules_fuzzing/blob/f6062a88d83463e2900e47bc218547ba046dad44/.bazelrc
 
 # Force the use of Clang for all builds.
-build --action_env=CC=clang-10
-build --action_env=CXX=clang++-10
+build --action_env=CC=clang-14
+build --action_env=CXX=clang++-14
 
-build --cxxopt=-std=c++14
-build --host_cxxopt=-std=c++14
+build --cxxopt=-std=c++20
+build --host_cxxopt=-std=c++20
 
 # The ASAN configuration suitable for C++ unit tests.
 build:asan --copt=-fsanitize=address

.bazelversion

@@ -1 +1 @@
-4.0.0
+4.0.0

script/ci.sh

@@ -16,5 +16,8 @@
 #
 ################################################################################
 
-bazel build //...
-bazel test //... --test_output=errors
+# TODO: Remove these two lines after getting rid of python2 dependencies.
+apt-get upgrade
+apt-get -y install python
+bazelisk build //...
+bazelisk test //... --test_output=errors