Ruby 3.0 on macos fails - Libraries missing

I am trying to use Ruby 3.0 in my build matrix:

  - linux
  - osx

dist:      bionic
osx_image: xcode10.2

language: ruby

  - '2.5'
  - '2.6'
  - '2.7'
  - '3.0'

I am using the xcode10.2 build image since according to Ruby 3.0 is only available for Mac OS X >= 10.14.

RVM fails to install the image:

ruby-3.0.0 - #validate binary

Libraries missing for ruby-3.0.0: __rvm_ls. Refer to your system manual for installing libraries

Mounting remote ruby failed with status 10, stopping installation.

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