feat(core): add the infrastructure to allow constructs specific feature flags in cdk.json (#1407)

* Add Feature Flag Infrastructure

* Make class true singleton and add tests

* Add cloud-assembly-schema

* Sync cloud-assembly-schema versions

* remove aws-cdk-lib version number in peerDependencies

Author: biffgaut

THIRD_PARTY_LICENSE.txt

@@ -21,9 +21,9 @@ License: Apache-2.0
 Apache-2.0: @ampproject/[email protected]
 Apache-2.0: @aws-cdk/[email protected]
 Apache-2.0: @aws-cdk/[email protected]
-Apache-2.0: @aws-cdk/cloud-assembly-schema@48.3.0
+Apache-2.0: @aws-cdk/cloud-assembly-schema@48.9.0
 Apache-2.0: @aws-cdk/[email protected]
-Apache-2.0: @aws-cdk/integ-tests-alpha@2.210.0-alpha.0
+Apache-2.0: @aws-cdk/integ-tests-alpha@2.214.0-alpha.0
 Apache-2.0: @aws-crypto/[email protected]
 Apache-2.0: @aws-crypto/[email protected]
 Apache-2.0: @aws-crypto/[email protected]
@@ -131,7 +131,7 @@ Apache-2.0: @smithy/[email protected]
 Apache-2.0: @smithy/[email protected]
 Apache-2.0: @smithy/[email protected]
 Apache-2.0: @smithy/[email protected]
-Apache-2.0: aws-cdk-lib@2.210.0
+Apache-2.0: aws-cdk-lib@2.214.0
 Apache-2.0: [email protected]
 Apache-2.0: [email protected]
 Apache-2.0: [email protected]
@@ -394,7 +394,7 @@ MIT: [email protected]
 MIT: [email protected]
 MIT: [email protected]
 MIT: [email protected]
-MIT: [email protected].0
+MIT: [email protected].1
 MIT: [email protected]
 MIT: [email protected]
 MIT: [email protected]
@@ -508,6 +508,7 @@ MIT: [email protected]
 MIT: [email protected]
 MIT: [email protected]
 MIT: [email protected]
+MIT: [email protected]
 MIT: [email protected]
 MIT: [email protected]
 MIT: [email protected]
@@ -751,6 +752,7 @@ BSD-3-Clause: [email protected]
 BSD-3-Clause: [email protected]
 BSD-3-Clause: [email protected]
 BSD-3-Clause: [email protected]
+BSD-3-Clause: [email protected]
 BSD-3-Clause: [email protected]
 BSD-3-Clause: [email protected]
 BSD-3-Clause: [email protected]
@@ -826,5 +828,5 @@ License: (MIT OR CC0-1.0)
 *******************
 (MIT OR CC0-1.0): [email protected]
 
-Total libraries: 763
+Total libraries: 765