tests/bazel_test: delete legacy test framework (bazel-contrib#2304)

Does not work with newer versions of Bazel, and everything's been
migrated to go_bazel_test.

Fixes bazel-contrib#1959

WORKSPACE

@@ -75,10 +75,6 @@ load("@bazel_gazelle//:deps.bzl", "gazelle_dependencies")
 
 gazelle_dependencies()
 
-load("@io_bazel_rules_go//tests:bazel_tests.bzl", "test_environment")
-
-test_environment()
-
 load("@io_bazel_rules_go//tests/legacy/test_chdir:remote.bzl", "test_chdir_remote")
 
 test_chdir_remote()

tests/BUILD.bazel

@@ -1,22 +0,0 @@
-load(":bazel_tests.bzl", "md5_sum")
-
-md5_sum(
-    name = "all_rules_md5",
-    testonly = True,
-    srcs = [
-        "//go:all_rules",
-        "//go/tools/builders:all_builder_srcs",
-        "//proto:all_rules",
-    ],
-    visibility = ["//visibility:private"],
-)
-
-# Consuming the above md5_sum rule directly into the data deps of a sh_test results in the
-# files just not appearing, and the dependancy not triggering.
-# If we wrap it in a filegroup first however it just works.
-filegroup(
-    name = "rules_go_deps",
-    testonly = True,
-    srcs = [":all_rules_md5"],
-    visibility = ["//visibility:public"],
-)