fix(cloud-assembly-schema): bump the version number

I did not want to bump the version number previously because the CLI did
not yet *act* on the new definitions found inside the schema, and users
would get the error message:

```
This CDK CLI is not compatible with the CDK library used by your application. Please upgrade the CLI to the latest version.
```

For no benefit.

This was a mistake, because we use `jsonschema` to validate the contents
of the manifest file and now old versions of the CLI try and validate
new files using the old schema, and instead they get the error:

```
Invalid assembly manifest:
instance.artifacts.aws-cdk-lib/feature-flag-report.type is not one of enum values: none,aws:cloudformation:stack,cdk:tree,cdk:asset-manifest,cdk:cloud-assembly
instance.artifacts.aws-cdk-lib/feature-flag-report.properties requires property "templateFile"
instance.artifacts.aws-cdk-lib/feature-flag-report.properties requires property "file"
```

We will need another mechanism to achieve the goal of not requiring
people to upgrade their CLI unnecessarily; holding back the version
number is just exchanging one error message for a worse one.

Belatedly bump the version number here, so that we can release this
and reapply this change: aws/aws-cdk#34880

Author: rix0rrr

packages/@aws-cdk/cloud-assembly-schema/schema/version.json

@@ -1,4 +1,4 @@
 {
   "schemaHash": "4709e40bc5dd6ad7d2bb6c6bd0315c622b7f4aa07ee3af66ff07f9bc77fdf783",
-  "revision": 44
+  "revision": 45
 }