Bump authoring duration for async backing to 2s. (#5195)

Should be safe on all production network. 

I noticed that Paseo needs to be updated, it is lacking behind in a
couple of things.

Execution environment parameters should be updated to those of Polkadot:

```
[
      {
        MaxMemoryPages: 8,192
      }
      {
        PvfExecTimeout: [
          Backing
          2,500
        ]
      }
      {
        PvfExecTimeout: [
          Approval
          15,000
        ]
      }
    ]
  ]
  ```

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Co-authored-by: eskimor <[email protected]>