Whether the invocation of API Extractor was successful. For example, if
succeeded is false, then the build task would normally return a nonzero process exit code, indicating that the operation failed.
readonly succeeded: boolean;
Normally the operation "succeeds" if
warningCount are both zero. However if IExtractorInvokeOptions.localBuild is
true, then the operation "succeeds" if
errorCount is zero (i.e. warnings are ignored).