Update copyrights

examples/csharp/helloworld/GreeterClient/Program.cs

examples/csharp/helloworld/GreeterServer/Program.cs

examples/csharp/route_guide/RouteGuide/RouteGuideUtil.cs

examples/csharp/route_guide/RouteGuideClient/Program.cs

examples/csharp/route_guide/RouteGuideServer/Program.cs

...les/csharp/route_guide/RouteGuideServer/RouteGuideImpl.cs

examples/node/route_guide/route_guide_client.js

examples/node/route_guide/route_guide_server.js

examples/python/helloworld/run_client.sh

examples/python/helloworld/run_codegen.sh

examples/python/helloworld/run_server.sh

examples/python/route_guide/run_client.sh

examples/python/route_guide/run_codegen.sh

examples/python/route_guide/run_server.sh

src/core/security/jwt_verifier.c

src/core/security/jwt_verifier.h

src/core/transport/static_metadata.c

src/core/transport/static_metadata.h

test/core/httpcli/test_server.py

test/core/security/jwt_verifier_test.c