await result of creation

dist/index.js

@@ -1043,7 +1043,7 @@ class AWSBuildEnvironment {
                         { ParameterKey: 'Storage', ParameterValue: `${baseStackName}-storage` },
                         { ParameterKey: 'Version', ParameterValue: `hash` },
                     ],
-                });
+                }).promise();
                 core.info('created stack');
             }
             const CFState = yield CF.describeStacks(describeStackInput).promise();

src/model/remote-builder/aws-build-platform.ts

@@ -250,7 +250,7 @@ class AWSBuildEnvironment implements RemoteBuilderProviderInterface {
           { ParameterKey: 'Storage', ParameterValue: `${baseStackName}-storage` },
           { ParameterKey: 'Version', ParameterValue: `hash` },
         ],
-      });
+      }).promise();
       core.info('created stack');
     }
     const CFState = await CF.describeStacks(describeStackInput).promise();