Update git submodules

* Update plugins/singleusergroup from branch 'master'
  to bf9cb8d819da6e605485be3bf784045abde2387e
  - Merge branch 'stable-3.0'
    
    * stable-3.0:
      Fix the testAllNumericUserGroup all-numeric username
      Test all-numeric username
    
    Change-Id: Ia85c38a18e7ad26802873b2cbb2ce9db8f0f4bea
    
  - Merge branch 'stable-2.16' into stable-3.0
    
    * stable-2.16:
      Fix the testAllNumericUserGroup all-numeric username
      Test all-numeric username
    
    Change-Id: I26b459a5c835f1fbf8d3d07107881fb1952ecc27
    
  - Fix the testAllNumericUserGroup all-numeric username
    
    Bug: Issue 11498
    Change-Id: Iee6dc050f8d1e97920c3e105af7bd2a69479dcea
    
  - Merge branch 'stable-2.15' into stable-2.16
    
    * stable-2.15:
      Test all-numeric username
    
    Change-Id: Ie659c4e19b9258dcb5b4ada96305d47b591cd5b7
    
  - Test all-numeric username
    
    Verify that a username with all numbers works as expected
    and generates an equivalent group associated with it.
    
    Change-Id: Ie98181fdecbf196c320b8b9d0ca0c7bd88b0d238
    
diff --git a/plugins/singleusergroup b/plugins/singleusergroup
index db53979..bf9cb8d 160000
--- a/plugins/singleusergroup
+++ b/plugins/singleusergroup
@@ -1 +1 @@
-Subproject commit db5397931ed05e9aedd385d3ec1511b4a64d3ddc
+Subproject commit bf9cb8d819da6e605485be3bf784045abde2387e