Add uv resolver fallback for named ports, fix portability tests

build.yaml

src/core/ext/transport/chttp2/transport/chttp2_transport.c

src/core/lib/iomgr/pollset_uv.c

src/core/lib/iomgr/resolve_address_uv.c

src/core/lib/iomgr/tcp_client_uv.c

test/core/iomgr/tcp_client_uv_test.c

test/core/iomgr/tcp_server_uv_test.c

test/core/util/trickle_endpoint.c

tools/run_tests/generated/tests.json

tools/run_tests/run_tests_matrix.py