bazel: Add json_data and providers (#18086)

Signed-off-by: Ryan Northey <ryan@synca.io>

Mirrored from https://github.com/envoyproxy/envoy @ c74b352b29e3042ab35893e83d0e9b56ba67989f

bazel/BUILD

@@ -1,4 +1,6 @@
 load("@io_bazel_rules_go//proto:compiler.bzl", "go_proto_compiler")
+load("//:utils.bzl", "json_data")
+load(":repository_locations.bzl", "REPOSITORY_LOCATIONS_SPEC")
 
 licenses(["notice"])  # Apache 2
 
@@ -15,3 +17,8 @@ go_proto_compiler(
     valid_archive = False,
     visibility = ["//visibility:public"],
 )
+
+json_data(
+    name = "repository_locations",
+    data = REPOSITORY_LOCATIONS_SPEC,
+)