feat(cfnspec): cloudformation spec v50.0.0 (#17844)

Generated by running `./scripts/bump-cfnspec.sh`. Needed some additions required for #17840.

Closes #17858 (duplicate)

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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: robertd

packages/@aws-cdk/aws-amplifyuibuilder/.eslintrc.js

@@ -0,0 +1,3 @@
+const baseConfig = require('@aws-cdk/cdk-build-tools/config/eslintrc');
+baseConfig.parserOptions.project = __dirname + '/tsconfig.json';
+module.exports = baseConfig;

packages/@aws-cdk/aws-amplifyuibuilder/.gitignore

@@ -0,0 +1,19 @@
+*.js
+*.js.map
+*.d.ts
+tsconfig.json
+node_modules
+*.generated.ts
+dist
+.jsii
+
+.LAST_BUILD
+.nyc_output
+coverage
+.nycrc
+.LAST_PACKAGE
+*.snk
+nyc.config.js
+!.eslintrc.js
+!jest.config.js
+junit.xml