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.

cloud build: initialize support for running commands in Dockerfile

If the Dockerfile needs to run some command, that step fails unless
QEMU is set up properly first:
      failed to solve: rpc error: code = Unknown desc = failed to load
      LLB: runtime execution on platform linux/ppc64le not supported

multiarch windows fix

Most repos inherit the default BUILD_PLATFORMS, which includes
Windows, but don't have the necessary Dockerfile.Windows yet. To
simplify the rollout of multiarch image builds, Windows binary
building continues to be tested (i.e. BUILD_PLATFORMS remains
unchanged), but push-multiarch skips Windows if the Dockerfile.Windows
is missing.

It's not a real file and thus should better be marked as phony.

"make push-multiarch" matched both push-multiarch and push-%.  This
seems to be none-deterministic and in at least one
repo (external-provisioner), make picked the wildcard rule which then
failed because there is no "multiarch" command.

This ambiguity gets resolved by instantiating the wildcard rules only
for existing commands. The advantage also is that "make
push-no-such-command" will fail with an obvious "No rule to make
target 'push-no-such-command'" instead of attempting to build the
command.

cloud build: initial set of shared files

The approach taken here extends the existing support for
cross-compiling binaries on the build host and specifying the Go
compiler: Go is installed if needed (as in Prow testing), binaries are
build on the host, then one image is created for each platform, and
finally those are combined into a single multi-architecture image.