Bazelize bump

Previously, running the release version bump run book required Go
pre-installed. It is not the case in our Bazel CI images.

This PR adds Bazel support for the bumper binary.

.gitignore

@@ -1,3 +1,4 @@
 .idea
 bin/
 build/artifacts
+bazel-*

BUILD.bazel

@@ -0,0 +1,4 @@
+load("@bazel_gazelle//:def.bzl", "gazelle")
+
+# to regenerate BUILD files, run `bazel run //:gazelle -- -go_prefix github.com/cockroachdb/helm-charts build`
+gazelle(name = "gazelle")

WORKSPACE

@@ -0,0 +1,49 @@
+workspace(name = "com_github_coachroachdb_helm_charts")
+
+load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
+
+http_archive(
+    name = "io_bazel_rules_go",
+    sha256 = "8e968b5fcea1d2d64071872b12737bbb5514524ee5f0a4f54f5920266c261acb",
+    urls = [
+        "https://mirror.bazel.build/github.com/bazelbuild/rules_go/releases/download/v0.28.0/rules_go-v0.28.0.zip",
+        "https://github.com/bazelbuild/rules_go/releases/download/v0.28.0/rules_go-v0.28.0.zip",
+    ],
+)
+
+http_archive(
+    name = "bazel_gazelle",
+    sha256 = "62ca106be173579c0a167deb23358fdfe71ffa1e4cfdddf5582af26520f1c66f",
+    urls = [
+        "https://mirror.bazel.build/github.com/bazelbuild/bazel-gazelle/releases/download/v0.23.0/bazel-gazelle-v0.23.0.tar.gz",
+        "https://github.com/bazelbuild/bazel-gazelle/releases/download/v0.23.0/bazel-gazelle-v0.23.0.tar.gz",
+    ],
+)
+
+load("@io_bazel_rules_go//go:deps.bzl", "go_register_toolchains", "go_rules_dependencies")
+load("@bazel_gazelle//:deps.bzl", "gazelle_dependencies", "go_repository")
+
+go_rules_dependencies()
+go_register_toolchains(version = "1.18")
+gazelle_dependencies()
+
+go_repository(
+    name = "in_gopkg_yaml_v3",
+    build_file_proto_mode = "disable_global",
+    importpath = "gopkg.in/yaml.v3",
+    sha256 = "5169b5625d3c351f13e8a4ec4802f709072701b441ed92181c6051ece53615a9",
+    strip_prefix = "gopkg.in/[email protected]",
+    urls = [
+        "https://storage.googleapis.com/cockroach-godeps/gomod/gopkg.in/yaml.v3/in_gopkg_yaml_v3-v3.0.0-20210107192922-496545a6307b.zip",
+    ],
+)
+go_repository(
+    name = "com_github_masterminds_semver_v3",
+    build_file_proto_mode = "disable_global",
+    importpath = "github.com/Masterminds/semver/v3",
+    sha256 = "0a46c7403dfeda09b0821e851f8e1cec8f1ea4276281e42ea399da5bc5bf0704",
+    strip_prefix = "github.com/Masterminds/semver/[email protected]",
+    urls = [
+        "https://storage.googleapis.com/cockroach-godeps/gomod/github.com/Masterminds/semver/v3/com_github_masterminds_semver_v3-v3.1.1.zip",
+    ],
+)

build/BUILD.bazel

@@ -0,0 +1,29 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_binary", "go_library")
+
+go_library(
+    name = "lib",
+    srcs = ["bump.go"],
+    importpath = "",
+    visibility = ["//visibility:private"],
+    deps = [
+        "@com_github_masterminds_semver_v3//:semver",
+        "@in_gopkg_yaml_v3//:yaml_v3",
+    ],
+)
+
+go_binary(
+    name = "build",
+    embed = [":build_lib"],
+    visibility = ["//visibility:public"],
+)
+
+go_library(
+    name = "build_lib",
+    srcs = ["bump.go"],
+    importpath = "github.com/cockroachdb/helm-charts/build",
+    visibility = ["//visibility:private"],
+    deps = [
+        "@com_github_masterminds_semver_v3//:semver",
+        "@in_gopkg_yaml_v3//:yaml_v3",
+    ],
+)