feat(actions-runner-controller): update the legacy ARC (#513)

- this includes some new functionality such as:
  - allowing modification of var-run mount maximum size limit
  - allowing more Docker config options

Author: chrisminton

libs/actions-runner-controller/config.jsonnet

@@ -2,7 +2,7 @@ local config = import 'jsonnet/config.jsonnet';
 
 local versions = [
   {output: '0.26', version: '0.26.0', legacy: true},
-  {output: '0.27', version: '0.27.4', legacy: true},
+  {output: '0.27', version: '0.27.6', legacy: true},
   {output: '0.4', version: 'gha-runner-scale-set-0.4.0'},
   {output: '0.5', version: 'gha-runner-scale-set-0.5.0'},
 ];