chore(apprunner): remove unnecessary dependency (#18631)

We forgot to remove this dependency when we migrated over to assertions. The assertions dependency is already added, so just removing this one.

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Author: kaizencc

packages/@aws-cdk/aws-apprunner/package.json

@@ -83,7 +83,6 @@
   },
   "license": "Apache-2.0",
   "devDependencies": {
-    "@aws-cdk/assert-internal": "0.0.0",
     "@aws-cdk/assertions": "0.0.0",
     "@aws-cdk/cdk-build-tools": "0.0.0",
     "@aws-cdk/cdk-integ-tools": "0.0.0",