fix(cfnspec): make EndpointConfiguration of AWS::Serverless::Api a un…

…ion type

A recent update to the SAM spec (#15311)
changed the EndpointConfiguration property of AWS::Serverless::Api
to have a complex type.
However, that is a breaking change compared to the previous, string, type.
I consulted with the SAM team, and it turns out the property accepts both a string and the complex type.
Given that, patch our SAM spec to make EndpointConfiguration a union type.

packages/@aws-cdk/aws-sam/test/api.test.ts

@@ -0,0 +1,44 @@
+import '@aws-cdk/assert-internal/jest';
+import * as cdk from '@aws-cdk/core';
+import * as sam from '../lib';
+
+describe('AWS::Serverless::Api', () => {
+  let stack: cdk.Stack;
+  beforeEach(() => {
+    stack = new cdk.Stack();
+  });
+
+  test('can be created by passing a complex type to EndpointConfiguration', () => {
+    new sam.CfnApi(stack, 'Api', {
+      stageName: 'prod',
+      definitionBody: {
+        body: 'definitionBody',
+      },
+      endpointConfiguration: {
+        type: 'GLOBAL',
+      },
+    });
+
+    expect(stack).toHaveResourceLike('AWS::Serverless::Api', {
+      StageName: 'prod',
+      EndpointConfiguration: {
+        Type: 'GLOBAL',
+      },
+    });
+  });
+
+  test('can be created by passing a string to EndpointConfiguration', () => {
+    new sam.CfnApi(stack, 'Api', {
+      stageName: 'prod',
+      definitionBody: {
+        body: 'definitionBody',
+      },
+      endpointConfiguration: 'GLOBAL',
+    });
+
+    expect(stack).toHaveResourceLike('AWS::Serverless::Api', {
+      StageName: 'prod',
+      EndpointConfiguration: 'GLOBAL',
+    });
+  });
+});

packages/@aws-cdk/cfnspec/spec-source/901_SAM_Api_EndpointConfiguration_patch.json

@@ -0,0 +1,29 @@
+{
+  "ResourceTypes": {
+    "AWS::Serverless::Api": {
+      "Properties": {
+        "EndpointConfiguration": {
+          "patch": {
+            "description": "Make the EndpointConfiguration property of AWS::Serverless::Api have a union type",
+            "operations": [
+              {
+                "op": "add",
+                "path": "/PrimitiveTypes",
+                "value": ["String"]
+              },
+              {
+                "op": "add",
+                "path": "/Types",
+                "value": ["EndpointConfiguration"]
+              },
+              {
+                "op": "remove",
+                "path": "/Type"
+              }
+            ]
+          }
+        }
+      }
+    }
+  }
+}