Error when loading on MacOS 11
All dependencies installed. This issue affects cl-sdl2 as well. Any clue how to get around this?

```
% sbcl
This is SBCL 2.1.3, an implementation of ANSI Common Lisp.
More information about SBCL is available at <http://www.sbcl.org/>.

SBCL is free software, provided as is, with absolutely no warranty.
It is mostly in the public domain; some portions are provided under
BSD-style licenses.  See the CREDITS and COPYING files in the
distribution for more information.
* (ql:quickload 'sketch)
To load "sketch":
  Load 1 ASDF system:
    sketch
; Loading "sketch"
...
debugger invoked on a LOAD-FOREIGN-LIBRARY-ERROR in thread
#<THREAD "main thread" RUNNING {1004AE81C3}>:
  Unable to find framework OpenGL

Type HELP for debugger help, or (SB-EXT:EXIT) to exit from SBCL.

restarts (invokable by number or by possibly-abbreviated name):
  0: [RETRY                        ] Try loading the foreign library again.
  1: [USE-VALUE                    ] Use another library instead.
  2: [TRY-RECOMPILING              ] Recompile library and try loading it again
  3: [RETRY                        ] Retry
                                     loading FASL for #<CL-SOURCE-FILE "cl-opengl" "gl" "library">.
  4: [ACCEPT                       ] Continue, treating
                                     loading FASL for #<CL-SOURCE-FILE "cl-opengl" "gl" "library">
                                     as having been successful.
  5:                                 Retry ASDF operation.
  6: [CLEAR-CONFIGURATION-AND-RETRY] Retry ASDF operation after resetting the
                                     configuration.
  7:                                 Retry ASDF operation.
  8:                                 Retry ASDF operation after resetting the
                                     configuration.
  9: [ABORT                        ] Give up on "sketch"
 10: [REGISTER-LOCAL-PROJECTS      ] Register local projects and try again.
 11:                                 Exit debugger, returning to top level.

(CFFI::FL-ERROR "Unable to find framework ~A" "OpenGL")
   source: (ERROR 'LOAD-FOREIGN-LIBRARY-ERROR :FORMAT-CONTROL CONTROL
                  :FORMAT-ARGUMENTS ARGUMENTS)
0]
```