Change Lab, CD4 COUNT Data to CD4 COUNT in dashboard.json

[jmgihana]

@sudhamshk @bharatak @maheshongithub @mogoodrich,
"Lab, CD4 COUNT Data" should be changed to "CD4 COUNT" for some reason the CD4 column is not displayed on the lab serology table until you change the configuration to point to the "CD4 COUNT" concept.

`
"conceptNames": [

        "Lab, Hepatitis B antigen test result",

        "Lab, Hepatitis C antibody test result",

        "HIV VIRAL LOAD",

       "**Lab, CD4 COUNT Data**"
      ]
    }
  },

`