[feature] "FindSoftware" implementation for KeyValue

[pxp928]

Is your feature request related to a problem? Please describe.
Currently FindSoftware has been implemented for the arango backend and the ENT backend but not for the Keyvalue backend.

This needs to be completed such that the demo can utilize this feature.

Describe the solution you'd like
Implementation on the keyvalue backend that does a "contains" search on pkgName, sourceName and artifact and return all that match.

Additional context
An example would look like the following (in graphQL playground):

query FindCurl {
  findSoftware(searchText: "curl") {
    __typename
    ... on Package {
      type
      namespaces {
        namespace
        names {
          name
        }
      }
    }
  }
}

This yields succinct results of just 27 relevant curl software - both packages and libraries, from debian, alpine, pycurl, rpm/amzn, etc.

{
  "data": {
    "findSoftware": [
      {
        "__typename": "Package",
        "type": "alpine",
        "namespaces": [
          {
            "namespace": "",
            "names": [
              {
                "name": "libcurl"
              }
            ]
          }
        ]
      },
      {
        "__typename": "Package",
        "type": "alpine",
        "namespaces": [
          {
            "namespace": "",
            "names": [
              {
                "name": "curl"
              }
            ]
          }
        ]
      },
     …TRUNCATED
      {
        "__typename": "Package",
        "type": "deb",
        "namespaces": [
          {
            "namespace": "ubuntu",
            "names": [
              {
                "name": "libcurl4-openssl-dev"
              }
            ]
          }
        ]
      }
    ]
  }
}

[nathannaveen]

I would like to work on this.