Add cloud sql proxy to admin tools deployment [Issue #263]

[skyfoxs]

What was changed

Add Cloud SQL proxy sidecar to the admin tools deployment.

Why?

To make Cloud SQL proxy available to the admin tools pod. So we can use the temporal-cassandra-tool and temporal-sql-tool to connect to the database like the others deployed by server-deployment.yaml and don't have to build it on our machine.

Checklist

1. Closes Close #263

2. How was this tested: Set up and install with sidecar containers as usual. Then shell into admin-tools and connect database with temporal-sql-tool.

3. Any docs updates needed? No

[CLAassistant]

All committers have signed the CLA.

[tsurdilo]

@skyfoxs thanks for the PR! Could you link it to an existing issue, or open a new one so it can be tracked? Thanks!

[skyfoxs]

@tsurdilo done

[tsurdilo]

This looks good to me. @underrun can you please also take a look? Thanks!

[mnichols]

Just wanted to point out this sidecar support (regardless of whether cloudsqlproxy is the intent) is already in other temporal service helm charts (https://github.com/temporalio/helm-charts/pull/107). Maybe that'll help merge it in :)

[kuzmik]

Any chance we can get this merged? I need it myself!

Also the sidecar is needed in the schema-setup jobs, since they require access to cloudsql as well; I'll see about adding that and making a PR for it.

[peter-c-larsson]

Any update on this and did you get around to making PR for the changes @kuzmik ?

[kuzmik]

Any update on this and did you get around to making PR for the changes @kuzmik ?

We worked around it by adding extra sidecars in the jsonnet (we use argo to manage k8s deployments, and the jsonnet repo loads helm charts and adapts them via code).

Originally I had adapted this PR to include the sidecars https://github.com/temporalio/helm-charts/pull/259/files; but since we generally prefer not to modify the helm charts in our repo if we can avoid it, I converted it to the sonnet stuff.

local k = import 'ksonnet-util/kausal.libsonnet';

(import './config.libsonnet')
+ {
  local c = $._config.temporal,
  local deployment = k.apps.v1.deployment,

  temporal+: {
    deployment_temporal_admintools+:
      deployment.spec.template.spec.withContainersMixin(c.containerCSP)
      + deployment.spec.withMinReadySeconds(10)
      + c.mysqlCSISecretMount,

for example.