feat: Add initial dockerfile

[roninjin10]

We want to be able to distribute mocktimism via a docker image. Add dockerfile to be used for this and CI

• Add initial dockerfile to build mocktimism as a docker image

Addresses first 2 items in https://github.com/ethereum-optimism/mocktimism/issues/27

[roninjin10]

Current dependencies on/for this PR:

• 10-18-feat_Add_cli_action_config
  • PR #41 👈
  • PR #46
  • PR #42
    • PR #44
    • PR #45
    • PR #43
    • PR #39
    • PR #53
      • PR #54
      • PR #55
        • PR #56
        • PR #57

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[roninjin10]

Related to https://github.com/ethereum-optimism/mocktimism/issues/11