Add ALIBUILD_VERSION to the prefer_system_check environment (#1002)

Author: ktf

alibuild_helpers/build.py

@@ -506,7 +506,10 @@ def doBuild(args, parser):
 
   install_wrapper_script("git", workDir)
 
-  extra_env = {"ALIBUILD_CONFIG_DIR": "/alidist" if args.docker else os.path.abspath(args.configDir)}
+  extra_env = {
+    "ALIBUILD_CONFIG_DIR": "/alidist" if args.docker else os.path.abspath(args.configDir),
+    "ALIBUILD_VERSION": __version__ or "unknown"
+  }
   extra_env.update(dict([e.partition('=')[::2] for e in args.environment]))
 
   with DockerRunner(args.dockerImage, args.docker_extra_args, extra_env=extra_env, extra_volumes=[f"{os.path.abspath(args.configDir)}:/alidist:ro"] if args.docker else []) as getstatusoutput_docker: