Add day of year plot to explore tab

[cristinamullin]

Is your feature request related to a problem? Please describe.

This issue cannot be completed until the figure function is developed. See: USEPA/EPATADA#477

Mock ups, page 16 (outdated but still relevant)
https://usepa.sharepoint.com/sites/WQPDataAssessmentTeam/Shared%20Documents/Forms/AllItems.aspx?id=%2Fsites%2FWQPDataAssessmentTeam%2FShared%20Documents%2FGeneral%2FTADA%20Dev%2FRShiny%2FTADA%20Module%201%20Mockups%2002252022%2Epdf&viewid=deb12f0b%2D3d2c%2D4694%2Dbe22%2D7d262f785cce&parent=%2Fsites%2FWQPDataAssessmentTeam%2FShared%20Documents%2FGeneral%2FTADA%20Dev%2FRShiny

Describe the solution you'd like

Incorporate plot into "Explore" tab

New features should include all of the following work:

• Create the function/code.

• Document all code using comments to describe what is does.

• Create tests.