This PR installs snapshot CRDs and rbac rules from the repo
and installs snapshot controller from a local image if it is
a PR in external-snapshotter repo.
Otherwise it uses main or a stable version.

Cleanup

Update snapshot CRD version

prow.sh: only run alpha tests for latest Kubernetes release

prow.sh: work around "kind build node-image" failure

Kind 0.9.0 accesses the "bazel-out" directory with a relative path,
which only works when the command is invoked inside the Kubernetes
source code
directory (https://github.com/kubernetes-sigs/kind/issues/1910).

Commit 7bcee13d added alpha feature gates for Kubernetes 1.19 in
the CSI_PROW_E2E_ALPHA_GATES_LATEST variable based on the comment in
https://github.com/kubernetes-csi/external-provisioner/pull/493#discussion_r502663402
that alpha testing only runs for the latest Kubernetes.

But some components (like external-health-monitor) are configured with
a single Prow job which runs the default set of tests on a stable
Kubernetes release (currently 1.17). Those tests used to include alpha
testing which then broke during Kind cluster startup because the
Kubernetes 1.19 feature gates weren't recognized by 1.17.

The solution is to disable alpha testing for Kubernetes != latest in
the default set of tests.

Add go ldflags using LDFLAGS at the time of compilation

prow.sh: update to kind 0.9, support Kubernetes 1.19

kind 0.9 adds support for recent Kubernetes releases like 1.19 and
simplifies configuration of feature gates and runtime config.

With Kubernetes 1.19, new feature gates were introduced which might
become relevant for the alpha Prow jobs.

The updated kind release comes with images for different Kubernetes
releases than the one before. To avoid breaking existing jobs,
the script now picks kind images automatically. As an additional
bonus, it then uses images with hash, i.e. it's less likely to break
if those image tags change because of a future kind release.

Bazel makes sense in the Prow jobs because those often get invoked
with a pre-populated Bazel cache. But local invocation don't need it
and now can turn it off with CSI_PROW_USE_BAZEL=false.

Update to snapshot-controller v3.0.0

Only set staging registry when running canary job

Update release process

Use staging registry for canary tests

Kubernetes 1.19 fixes

It used to be necessary to override from where the E2E suite came on a
case-by-case basis (initially, testing was using a more recent suite
against an older Kubernetes). This should never become necessary again
and the lack of a specific entry for 1.18 already had the unintended
effect that Kubernetes 1.18 was tested with the suite from master, so
overall it is better to always use the E2E suite which matches
Kubernetes.

Kubernetes 1.19.0 uses Go 1.15, but refers to it as 1.15.0. This broke
both the check whether we need to install 1.15 (because "go version"
reports 1.15, which didn't match 1.15.0) and then downloading the
release archive (because the URL also only uses 1.15).

switch to Go 1.15

Go 1.15 was released and is the major version that Kubernetes 1.19.0
is going to use. There are probably bugs in the older 1.13.3 that were
fixed, so we should update.

Add steps on promoting release images

cloud build: bump timeout in Prow job

filter-junit: Fix gofmt error

Signed-off-by: Animesh Kumar <animuz111@gmail.com>

filter-junit: Fix golint error

Signed-off-by: Animesh Kumar <animuz111@gmail.com>

prow.sh: enable building arm64 image

cloud build: k8s-staging-sig-storage

As discussed in https://github.com/kubernetes/k8s.io/pull/943, we want
to consolidate under k8s-staging-sig-storage.