Another way to get era points for a session

[sahilnanda1995]

Currently not working, but for future it will significantly reduce load. Need to keep a check on it with newer versions of the polkadot/api module.

"authoredBlocks": {
      "name": "AuthoredBlocks",
      "modifier": 1,
      "type": {
        "DoubleMap": {
          "hasher": "Blake2_256",
          "key1": "SessionIndex",
          "key2": "ValidatorId",
          "value": "u32",
          "key2Hasher": "Blake2_256"
        }
      },
      "fallback": "0x00000000",
      "documentation": [
        " For each session index, we keep a mapping of `T::ValidatorId` to the",
        " number of blocks authored by the given authority."
      ],
      "storage": {
        "method": "AuthoredBlocks",
        "prefix": "ImOnline",
        "section": "imOnline"
      }
    }
  }