fix(app-delivery): fix integ test not building

[jogold]

Replaced cdk.Secret by cdk.SecretValue.

Although JSII build is failing for app-delivery, the Travis build is passing. This behavior can be seen on master:
https://travis-ci.org/awslabs/aws-cdk/builds/516243105#L1591
https://travis-ci.org/awslabs/aws-cdk/builds/516223708#L1591

The same kind of issue can be seen here https://travis-ci.org/awslabs/aws-cdk/builds/514128209#L1573 where the JSII build for aws-codebuild fails but not the Travis build.

Linked to the updated version of jsii? May be worth opening a specific issue...

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Pull Request Checklist

• Testing
  • Unit test added (prefer not to modify an existing test, otherwise, it's probably a breaking change)
  • CLI change?: coordinate update of integration tests with team
  • cdk-init template change?: coordinated update of integration tests with team
• Docs
  • jsdocs: All public APIs documented
  • README: README and/or documentation topic updated
• Title and Description
  • Change type: title prefixed with fix, feat will appear in changelog
  • Title: use lower-case and doesn't end with a period
  • Breaking?: last paragraph: "BREAKING CHANGE: <describe what changed + link for details>"
  • Issues: Indicate issues fixed via: "Fixes #xxx" or "Closes #xxx"
• Sensitive Modules (requires 2 PR approvers)
  • IAM Policy Document (in @aws-cdk/aws-iam)
  • EC2 Security Groups and ACLs (in @aws-cdk/aws-ec2)
  • Grant APIs (only if not based on official documentation with a reference)

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By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license.

[eladb]

How are our builds not broken?

[jogold]

Don't know... was not able to reproduce this bug. jsii? lerna? Travis? What about the builds on master with CodeBuild, same bug?

[jogold]

@eladb I was able to reproduce and it seems that when there are only compilation errors (Compilation errors prevented the JSII assembly from being created) from JSII then the build (cdk-build) succeeds (the error message is displayed but the exit code is 0). When there are both compilation (Compilation errors prevented the JSII assembly from being created) and type model errors (Type model errors prevented the JSII assembly from being created) then cdk-build fails. Compilation errors without type model errors are less common and could explain why this was not seen in the builds sooner.

Could this come from the changes introduced here aws/jsii#383 where the behavior in case of compilation errors was changed?

[jogold]

Here's another example of a build that should be failing already here https://travis-ci.org/awslabs/aws-cdk/builds/517283134#L1395, here https://travis-ci.org/awslabs/aws-cdk/builds/517283134#L1414 and here https://travis-ci.org/awslabs/aws-cdk/builds/517283134#L1461 but utimately fails only when the first type error occurs here https://travis-ci.org/awslabs/aws-cdk/builds/517283134#L1489

[eladb]

#2200