C-ares status is not ARES_SUCCESS: Misformatted domain name

This affects all portable runners (Flink, Spark, Dataflow Python streaming). It does not appear to cause pipelines to fail.

Exception in thread read_grpc_client_inputs:
Traceback (most recent call last):
File "/usr/local/lib/python3.7/threading.py", line 926, in _bootstrap_inner
self.run()
File "/usr/local/lib/python3.7/threading.py", line 870, in run
self._target(*self._args, **self._kwargs)
File "/usr/local/lib/python3.7/site-packages/apache_beam/runners/worker/data_plane.py", line 545, in <lambda>
target=lambda: self._read_inputs(elements_iterator),
File "/usr/local/lib/python3.7/site-packages/apache_beam/runners/worker/data_plane.py", line 528, in _read_inputs
for elements in elements_iterator:
File "/usr/local/lib/python3.7/site-packages/grpc/channel.py", line 388, in _next
return self._next()
File "/usr/local/lib/python3.7/site-packages/grpc/_channel.py", line 365, in _next
raise self
grpc._channel._Rendezvous: <_Rendezvous of RPC that terminated with:
status = StatusCode.UNAVAILABLE
details = "DNS resolution failed"
debug_error_string = "{"created":"@1587426512.443144965","description":"Failed to pick subchannel","file":"src/core/ext/filters/client_channel/client_channel.cc","file_line":3876,"referenced_errors":[{"created":"@1587426512.443142363","description":"Resolver transient failure","file":"src/core/ext/filters/client_channel/resolving_lb_policy.cc","file_line":263,"referenced_errors":[{"created":"@1587426512.443141313","description":"DNS resolution failed","file":"src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.cc","file_line":357,"grpc_status":14,"referenced_errors":[{"created":"@1587426512.443136986","description":"C-ares status is not ARES_SUCCESS: Misformatted domain name","file":"src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.cc","file_line":244,"referenced_errors":[

{"created":"@1587426512.443126564","description":"C-ares status is not ARES_SUCCESS: Misformatted domain name","file":"src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.cc","file_line":244}

]}]}]}]}"
>