Use go modules

[hidekazuna]

What this PR does / why we need it:

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #381

Special notes for your reviewer:

1. Please confirm that if this PR changes any image versions, then that's the sole change this PR makes.

Release note:

[hidekazuna]

I referred to kubernetes-sigs/cluster-api-provider-azure#231.

[jichenjc]

previously it's branch release-0.1 now it's a tag ? just want to make sure understand is correct

[hidekazuna]

Yes, The go.mod file generally use semantics versions which is introduced by tagging a revision in the underlying source repository.
https://golang.org/cmd/go/#hdr-Pseudo_versions

[jichenjc]

/approve

@sbueringer do you need this to be merged after #382 ?

[jichenjc]

I ran locally and able to create a cluster

[sbueringer]

@jichenjc if it's okay let's merge #401 then go modules. But I think we have consensus to merge the LB PR now so you can merge both now

[jichenjc]

@hidekazuna

run this locally for 'make test' and saw additional changes like following, I guess you might need commit this?

+++ b/config/crds/openstackproviderconfig_v1alpha1_openstackclusterproviderspec.yaml
@@ -87,6 +87,10 @@ spec:
                       ipVersion:
                         format: int64
                         type: integer
+                      ipv6AddressMode:
+                        type: string
+                      ipv6RaMode:
+                        type: string
                       limit:
                         format: int64
                         type: integer
diff --git a/vendor/sigs.k8s.io/cluster-api/BUILD.bazel b/vendor/sigs.k8s.io/cluster-api/BUILD.bazel
deleted file mode 100644
index be252e22..00000000
--- a/vendor/sigs.k8s.io/cluster-api/BUILD.bazel
+++ /dev/null
@@ -1,21 +0,0 @@
-load("@bazel_gazelle//:def.bzl", "gazelle")
-load("//build:run_in_workspace_with_goroot.bzl", "workspace_binary")
-
-# gazelle:prefix sigs.k8s.io/cluster-api
-# gazelle:proto disable_global
-gazelle(
-    name = "gazelle",
-    external = "vendored",
-)
-
-workspace_binary(
-    name = "lint",
-    args = ["run"],
-    cmd = "@com_github_golangci_golangci-lint//cmd/golangci-lint",
-)
-

[jichenjc]

/approve cancel

[hidekazuna]

@hidekazuna

run this locally for 'make test' and saw additional changes like following, I guess you might need commit this?

@jichenjc I resolved conflict. check again, please.

[jichenjc]

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: hidekazuna, jichenjc

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