JLab 0.34.x non-compatibility

At the present state BeakerX does not work for me OOB under `jupyterlab` 0.34.x, much with my best efforts to integrate it into my daily workflow. Even with a trivial patch of (on top of boosting the `devDependencies`), with which it ultimately compiles:
```diff
--- a/lab/src/theme/index.ts
+++ b/lab/src/theme/index.ts
@@ -28,6 +28,7 @@ export const themeLightPlugin: JupyterLa
activate: function(app: JupyterLab, manager: IThemeManager) {
manager.register({
name: 'BeakerX Light',
+ isLight: true,
load: (): Promise => {
return new Promise((resolve, reject) => {
Promise.all([
@@ -54,6 +55,7 @@ export const themeDarkPlugin: JupyterLab
activate: function(app: JupyterLab, manager: IThemeManager) {
manager.register({
name: 'BeakerX Dark',
+ isLight: false,
load: (): Promise => {
document.body.classList.add('bx-dark-theme')
return new Promise((resolve, reject) => {
```
I'm getting almost every 404 error seen in the `jupyter-lab --debug` log on requests which simply should not be there.