build: change backend NONE option to DISABLE

due to errors in GHA

Author: DavidPL1

.github/workflows/ci.yaml

@@ -21,7 +21,7 @@ jobs:
       fail-fast: false
       matrix:
         distro: [noetic, one]
-        render_backend: [GLFW, OSMESA, EGL, NONE]
+        render_backend: [GLFW, OSMESA, EGL, DISABLE]
         mujoco: [3.2.0]
         include:
           - distro: noetic

mujoco_ros/cmake/ConfigureRenderBackend.cmake

@@ -3,7 +3,7 @@ include_guard()
 find_library(GLFW libglfw.so.3) # Find GLFW3 for GUI
 
 set(RENDER_BACKEND "ANY" CACHE STRING "Choose rendering backend")
-set_property(CACHE RENDER_BACKEND PROPERTY STRINGS "ANY" "GLFW" "EGL" "OSMESA" "NONE")
+set_property(CACHE RENDER_BACKEND PROPERTY STRINGS "ANY" "GLFW" "EGL" "OSMESA" "DISABLE")
 
 set(NO_GLFW OFF)
 set(NO_EGL OFF)
@@ -21,7 +21,7 @@ elseif (RENDER_BACKEND STREQUAL "OSMESA")
   set(NO_GLFW ON)
   set(NO_EGL ON)
   message(WARNING "GLFW and EGL disabled!")
-elseif (RENDER_BACKEND STREQUAL "NONE")
+elseif (RENDER_BACKEND STREQUAL "DISABLE")
   set(NO_GLFW ON)
   set(NO_EGL ON)
   set(NO_OSMESA ON)