fix(bitbucket): fix rebasing mistakes in bitbucket backend and deps (#1522)

packages/netlify-cms-lib-util/src/index.js

@@ -5,3 +5,4 @@ export localForage from './localForage';
 export { resolvePath, basename, fileExtensionWithSeparator, fileExtension } from './path';
 export { filterPromises, resolvePromiseProperties, then } from './promise';
 export unsentRequest from './unsentRequest';
+export { filterByPropExtension, parseResponse, responseParser } from './backendUtil';