chore!: upgrade to cdktf 0.20.0 (#298)

This PR initiates the upgrade of CDKTF from version `0.19.0` to version
`0.20.0`.
Unfortunately, not everything can be automated, and the following steps
need to be completed manually:
 
- [x] Update `@cdktf/provider-null` to a version compatible with
`[email protected]`
[here](https://github.com/cdktf/cdktf-tf-module-stack/blob/106036d2d6b65652b68dabb2648b1f7980c6421d/.projenrc.ts#L78).
Look up the version
[here](https://github.com/cdktf/cdktf-provider-null/releases/).
- [x] Update `@cdktf/provider-random` to a version compatible with
`[email protected]`
[here](https://github.com/cdktf/cdktf-tf-module-stack/blob/106036d2d6b65652b68dabb2648b1f7980c6421d/.projenrc.ts#L79).
Look up the version
[here](https://github.com/cdktf/cdktf-provider-random/releases/).
- [x] Run `npx projen`
 
Please checkout this PR, complete the above steps, push the changes to
this branch, and then mark this PR as ready for review to complete the
upgrade. Thanks!

---------

Signed-off-by: team-tf-cdk <[email protected]>
Co-authored-by: Ansgar Mertens <[email protected]>

.projenrc.ts

@@ -42,7 +42,7 @@ const project = new ConstructLibraryCdktf({
     },
   },
   minMajorVersion: 1,
-  cdktfVersion: "0.19.0",
+  cdktfVersion: "0.20.0",
   description:
     "A drop-in replacement for cdktf.TerraformStack that lets you define Terraform modules as constructs" /* The description is just a string that helps people understand the purpose of the package. */,
   workflowGitIdentity: {
@@ -79,10 +79,10 @@ new AutoApprove(project);
 new Automerge(project);
 new UpgradeCDKTF(project);
 
-project.addPeerDeps("cdktf@>=0.19.0", "constructs@^10.0.25");
+project.addPeerDeps("cdktf@>=0.20.0", "constructs@^10.0.25");
 project.addDevDeps(
-  "@cdktf/provider-null@>=9.0.0",
-  "@cdktf/provider-random@>=10.0.0"
+  "@cdktf/provider-null@>=10.0.0",
+  "@cdktf/provider-random@>=11.0.0"
 );
 
 new JsiiDocgen(project, {

README.md

@@ -17,7 +17,7 @@ By using the software in this repository, you acknowledge that:
 
 ## Compatibility
 
-* `cdktf` >= 0.19.0
+* `cdktf` >= 0.20.0
 * `constructs` >= 10.0.25
 
 ## Available Packages