Simplify API usage when the caller has multiple values they wish
to make a slice from, allowing:

	Slice([]workflow.Value{v1, v2})

To be written as:

	Slice(v1, v2)

For cases where the caller has a slice, they can do Slice(s...),
which is only 3 extra characters compared to now.

This was motivated by further uses of Slice in an upcoming CL.

For golang/go#53537.

Change-Id: I820ba6eaaa0d833259fed7bb6cc66b12b3f25611
Reviewed-on: https://go-review.googlesource.com/c/build/+/414034
Reviewed-by: Carlos Amedee <carlos@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>
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The next step after joining the announcement mail and tweet tasks
is to append them to the end of the main existing release workflows.

This removes the need for the human release coordinator to manually
enter the Version (and, for minor releases, Secondary Version)
parameters, since that information is already automatically computed
as part of those workflows, and can be passed along.

Since the website update is not yet integrated into the release flow,
and as an initial safety check, add another "Wait to Announce" step
that must be approved by the release coordinator, before relui proceeds
to announce a recently published Go release.

This change adds, but doesn't yet enable, this functionality; it's
currently gated on the mergeCommTasksIntoReleaseWorkflows constant.

For golang/go#53537.

Change-Id: Id9046ae3de52da5ba49e4bcecda2ca427fd0e51c
Reviewed-on: https://go-review.googlesource.com/c/build/+/414035
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Carlos Amedee <carlos@golang.org>
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>

The workflow package requires all tasks to be referenced somehow, and
they weren't if the comms tasks were disabled.

For golang/go#53537.

Change-Id: Iafb60cb9a73d8e1583456cee3e9667150259338e
Reviewed-on: https://go-review.googlesource.com/c/build/+/416218
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Auto-Submit: Heschi Kreinick <heschi@google.com>
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Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>

CL 418789 added workflows to do a single minor release.
This adds corresponding support to the comm tasks.

Deal with the fact that the new single minor release kinds need more
communication parameters (for security information) in a verbose way
for now, and consider it as motivation to refactor the comm task API
to better fit relui's current needs in a followup change.

For golang/go#53537.

Change-Id: I99db09969151a3e83676ed2b59109011b53041c5
Reviewed-on: https://go-review.googlesource.com/c/build/+/419516
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>

The comm tasks proved to work well during the last release, so take the
next step of merging them into the main release workflow. This moves in
the direction of a Go release being fully completed by a relui workflow,
with all information necessary for the release automation to do its job
provided upfront.

For short term flexibility, keep the comm-less release workflows around
under a "[without comms]" prefix, so they're there without redeployment.
Balance it out by deleting the announce-only and tweet-only workflows
since those are the least useful by now.

For golang/go#53537.

Change-Id: I82af660c31ceb0045c953adbba9401c38245d4c0
Reviewed-on: https://go-review.googlesource.com/c/build/+/419515
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Javad Rajabzadeh <ja7ad@live.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>

The combined build+communication workflows have superseded the previous
separate workflows.

For golang/go#53537.

Change-Id: I380501aa80fbaa32334ef54cca11649e29dfcf26
Reviewed-on: https://go-review.googlesource.com/c/build/+/447295
Reviewed-by: Carlos Amedee <carlos@golang.org>
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
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