Step template with certificate parameter not supplied causes error when creating deployment

[MJRichardson]

Reproduction:

1. Create a step template with a certificate parameter
2. Create a project and add a step based off the template
3. Do not supply a value for the certificate parameter
4. Create a release
5. Attempt to deploy the release

Results:

An error similar to the following is thrown:

The given key was not present in the dictionary.
System.Collections.Generic.KeyNotFoundException
   at System.ThrowHelper.ThrowKeyNotFoundException()
   at System.Collections.Generic.Dictionary`2.get_Item(TKey key)
   at Octopus.Server.Orchestration.Deploy.Manifest.DeploymentManifestFactory.ExpandTypedActionTemplateParameters(VariableCollection variables, DeploymentProcess deploymentProcess, IActionTemplateVersionFinder actionTemplateVersionFinder)
   at Octopus.Server.Orchestration.Deploy.Manifest.DeploymentManifestFactory.CreateManifestVariables(String listenPrefixes, Deployment deployment, Project project, DeploymentProcess process, DeploymentEnvironment environment, Release release, Channel channel, ServerTask task, IList`1 environmentMachines, IList`1 environmentAccounts, IList`1 machinePolicies, RetentionPeriod tentacleRetentionPeriod, ProjectGroup projectGroup, User initiator, VariableCollection projectVariables, VariableCollection libraryVariables, Release previousRelease, Release previousReleaseForEnvironment, Deployment previousSuccessfulEnvironmentDeployment, Release currentReleaseForEnvironment, Tenant tenant, ICanonicalTagNameMapper tagNameMapper, VariableCollection tenantVariables, IActionTemplateVersionFinder actionTemplateVersionFinder, ICollection`1 certificates)
   at Octopus.Server.Orchestration.Deploy.DeploymentFactory.CreateDeployment(IRelationalTransaction transaction, Deployment deployment, User user, DateTimeOffset queueTime, Nullable`1 queueTimeExpiry, ILifecycleProgressionEvaluator lifecycleProgressionEvaluator, ILifecycleService lifecycleService, IDeploymentSummaryService deploymentSummaryService, Func`2 promptedVariableProvider)
...

Reported by https://secure.helpscout.net/conversation/373366748?folderId=557077 (private link)

[octoreleasebot]

Release Note: Resolved error creating deployment when certificate step-template parameters not supplied

[lock[bot]]

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