fix(aws-cdk-lib): upgrade version of ajv that triggers CVE scanners (#37022)

Upgrade `ajv` to `8.18.0`, which is version that is not vulnerable to a ReDoS attack anymore.

Note that CDK never had an actual vulnerability in the first place because the input was not attacker-controlled, but CVE scanners will flag this finding regardless.

This overrides the package in our repository, the dependency that gets installed at build time is bundled into the final `aws-cdk-lib` tarball.

Closes #36989

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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*

Author: rix0rrr

yarn.lock

@@ -5914,9 +5914,9 @@ ajv@^6, ajv@^6.12.4:
     uri-js "^4.2.2"
 
 ajv@^8.0.1, ajv@^8.17.1:
-  version "8.17.1"
-  resolved "https://registry.npmjs.org/ajv/-/ajv-8.17.1.tgz#37d9a5c776af6bc92d7f4f9510eba4c0a60d11a6"
-  integrity sha512-B/gBuNg5SiMTrPkC+A2+cW0RszwxYmn6VYxB/inlBStS5nx6xHIt/ehKRhIMhqusl7a8LjQoZnjCs5vhwxOQ1g==
+  version "8.18.0"
+  resolved "https://registry.npmjs.org/ajv/-/ajv-8.18.0.tgz#8864186b6738d003eb3a933172bb3833e10cefbc"
+  integrity sha512-PlXPeEWMXMZ7sPYOHqmDyCJzcfNrUr3fGNKtezX14ykXOEIvyK81d+qydx89KY5O71FKMPaQ2vBfBFI5NHR63A==
   dependencies:
     fast-deep-equal "^3.1.3"
     fast-uri "^3.0.1"