Bazel files are out of date

[johanbrandhorst]

The bazel up-to-date job just started failing: https://circleci.com/gh/grpc-ecosystem/grpc-gateway/3163

#!/bin/bash -eo pipefail
bazel run //:gazelle -- --mode=diff || (echo "ERROR: Bazel files out-of-date, please run \`bazel run :gazelle\`" >&2; exit 1)

Extracting Bazel installation...
Starting local Bazel server and connecting to it...
Loading: 
Loading: 0 packages loaded
Loading: 0 packages loaded
Loading: 0 packages loaded
INFO: SHA256 (https://github.com/bazelbuild/buildtools/archive/bf564b4925ab5876a3f64d8b90fab7f769013d42.zip) = b5d7dbc6832f11b6468328a376de05959a1a9e4e9f5622499d3bab509c26b46a
DEBUG: Rule 'com_github_bazelbuild_buildtools' indicated that a canonical reproducible form can be obtained by modifying arguments sha256 = "b5d7dbc6832f11b6468328a376de05959a1a9e4e9f5622499d3bab509c26b46a"
DEBUG: Call stack for the definition of repository 'com_github_bazelbuild_buildtools' which is a http_archive (rule definition at /root/.cache/_grpc_gateway_bazel/external/bazel_tools/tools/build_defs/repo/http.bzl:237:16):
 - /src/grpc-gateway/WORKSPACE:62:1
Analyzing: target //:gazelle (1 packages loaded, 0 targets configured)
Analyzing: target //:gazelle (11 packages loaded, 36 targets configured)
Analyzing: target //:gazelle (11 packages loaded, 36 targets configured)
Analyzing: target //:gazelle (11 packages loaded, 36 targets configured)
INFO: SHA256 (https://codeload.github.com/golang/tools/zip/bf090417da8b6150dcfe96795325f5aa78fff718) = 11629171a39a1cb4d426760005be6f7cb9b4182e4cb2756b7f1c5c2b6ae869fe
Analyzing: target //:gazelle (47 packages loaded, 6513 targets configured)
DEBUG: Rule 'org_golang_x_tools' indicated that a canonical reproducible form can be obtained by modifying arguments sha256 = "11629171a39a1cb4d426760005be6f7cb9b4182e4cb2756b7f1c5c2b6ae869fe"
DEBUG: Call stack for the definition of repository 'org_golang_x_tools' which is a http_archive (rule definition at /root/.cache/_grpc_gateway_bazel/external/bazel_tools/tools/build_defs/repo/http.bzl:237:16):
 - /root/.cache/_grpc_gateway_bazel/external/io_bazel_rules_go/go/private/repositories.bzl:206:9
 - /root/.cache/_grpc_gateway_bazel/external/io_bazel_rules_go/go/private/repositories.bzl:38:5
 - /src/grpc-gateway/WORKSPACE:19:1
ERROR: /root/.cache/_grpc_gateway_bazel/external/io_bazel_rules_go/BUILD.bazel:66:1: in go_context_data rule @io_bazel_rules_go//:go_context_data: 
Traceback (most recent call last):
	File "/root/.cache/_grpc_gateway_bazel/external/io_bazel_rules_go/BUILD.bazel", line 66
		go_context_data(name = 'go_context_data')
	File "/root/.cache/_grpc_gateway_bazel/external/io_bazel_rules_go/go/private/context.bzl", line 400, in _go_context_data_impl
		cc_common.configure_features(cc_toolchain = cc_toolchain, reque..., ...)
Incompatible flag --incompatible_require_ctx_in_configure_features has been flipped, and the mandatory parameter 'ctx' of cc_common.configure_features is missing. Please add 'ctx' as a named parameter. See https://github.com/bazelbuild/bazel/issues/7793 for details.
ERROR: Analysis of target '//:gazelle' failed; build aborted: Analysis of target '@io_bazel_rules_go//:go_context_data' failed; build aborted
INFO: Elapsed time: 13.172s
INFO: 0 processes.
FAILED: Build did NOT complete successfully (55 packages loaded, 6581 targets configured)
ERROR: Build failed. Not running target
FAILED: Build did NOT complete successfully (55 packages loaded, 6581 targets configured)
ERROR: Bazel files out-of-date, please run `bazel run :gazelle`
Exited with code 1

I assume we just need to update something.

CC @drigz @achew22