[BUG] Indentation left does not work any more in latest version

[android-outliner]

If you press the indentation right button, everything is ok. Indentation left does intent to the right instead of indent to the left.

In the latest RT-Editor Demo App the issue can be simply reproduced.

The reason seems to be this code in HorizontalRTToolbar.java (line 646):

        else if (id == R.id.toolbar_inc_indent) {
            mListener.onEffectSelected(Effects.INDENTATION, Helper.getLeadingMarging());
        }

        else if (id == R.id.toolbar_dec_indent) {
            mListener.onEffectSelected(Effects.INDENTATION, Helper.getLeadingMarging());     //**** minus missing ****
        }

For R.id.toolbar_dec_indent a minus is missing: -Helper.getLeadingMarging()

It worked in an older version. The error seems to be introduced when migrating to AndroidX. This is the problematic commit: https://github.com/1gravity/Android-RTEditor/commit/6982075b63cc1c488e176db2e8c60fd1e907c664

Unfortunately I can't stick to any older version because the Google Play Store complains the old version of org.greenrobot:eventbus:3.1.1 inside the RTEditor library when uploading my App.