chore: add sinon dep (#27596)

Add an explicit dependency on a version of sinon that we depend on in other packages. This version is what is used by `aws-cdk-lib` currently. This fixes an issue that occurs currently when installing @aws-cdk-testing/cli-integ in a directory that is not a git repository as described [in this issue](sinonjs/sinon#2557).

This doesn't occur during local development because yarn dedupes sinon to a version that intersects with the peerDep range taken by `ts-mock-imports` and versions depended on by other packages, such as `aws-cdk-lib`. Also it's in a git repo.


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packages/@aws-cdk-testing/cli-integ/package.json

@@ -49,6 +49,7 @@
     "npm": "^8.19.4",
     "p-queue": "^6.6.2",
     "semver": "^7.5.4",
+    "sinon": "^9.2.4",
     "ts-mock-imports": "^1.3.8",
     "yaml": "1.10.2",
     "yargs": "^17.7.2"