Fetch missions data

[dennis-every]

The following requirement was completed in this pull request:

• Fetch data from the Missions endpoint (https://api.spacexdata.com/v3/missions) when a user navigates to the Missions section.
• Once the data are fetched, dispatch an action to store the selected data in Redux store: mission_id, mission_name, description.
• Make sure you only dispatch those actions once and do not add data to store on every re-render (i.e. when changing views / using navigation).

[dfsalam]

Hi @dennis-every,

STATUS: APPROVED 😄

Your project is complete! There is nothing else to say other than... it's time to merge it :shipit: Congratulations! 🎉