[server] add feature flags for spicedb client options

[mustard-mh]

Description

[server] add feature flags for spicedb client options

The default value of the feature flag is undefined. If the feature flag is set to this value, we will use the default spicedb grpc client options, otherwise the value should be a valid json.

Related Issue(s)

Relates CLC-370

How to test

• Update value of FF , the value should be JSON.stringify grpc client options
  • with correct grpc client options - use new option
  • incorrect options - use default option
  • invalid value - use default option
• Check logs of server and see if spicedb grpc options / client changed

Documentation

Preview status

Gitpod was successfully deployed to your preview environment.

• 🏷️ Name - hw-clc-370
• 🔗 URL - hw-clc-370.preview.gitpod-dev.com/workspaces.
• 📚 Documentation - See our internal documentation for information on how to interact with your preview environment.
• 📦 Version - hw-CLC-370-gha.31461
• 🗒️ Logs - GCP Logs Explorer

Build Options

Build

• /werft with-werft
  Run the build with werft instead of GHA
• leeway-no-cache
• /werft no-test
  Run Leeway with --dont-test

Publish

• /werft publish-to-npm
• /werft publish-to-jb-marketplace

Installer

• analytics=segment
• with-dedicated-emulation
• workspace-feature-flags
  Add desired feature flags to the end of the line above, space separated

Preview Environment / Integration Tests

• /werft with-local-preview
  If enabled this will build install/preview
• /werft with-preview
• /werft with-large-vm
• /werft with-gce-vm
  If enabled this will create the environment on GCE infra
• /werft preemptible
  Saves cost. Untick this only if you're really sure you need a non-preemtible machine.
• with-integration-tests=all
  Valid options are all, workspace, webapp, ide, jetbrains, vscode, ssh. If enabled, with-preview and with-large-vm will be enabled.
• with-monitoring

/hold

[filiptronicek]

@mustard-mh because the API calls on the preview environment seem to be succeeding, I assume SpiceDB is doing fine. Could you update the description in the PR or in Linear to outline:

• why this is needed
• what options we'd like to use in other environments