Added energy model

[einfachMel]

Fixes #32

This PR ...

Added the DB-Model for the energy_model which contains details to the FINE model and the using dataset.

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Checklist

Checklist for Contributors

• Unit tests provided?
  Unit tests are needed for new features or to reproduce the bug solved by this PR.
• Documentation updated?
• Unit tests successful
• Code smells (flake8) checked

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[V3lop5]

• Changed yearly_co2_limit from int to float
• Made yearly_co2_limit optional

[codecov-commenter]

Codecov Report

Merging #44 (2770fd3) into main (87d42bd) will decrease coverage by 0.26%.
The diff coverage is 86.76%.

@@            Coverage Diff             @@
##             main      #44      +/-   ##
==========================================
- Coverage   91.28%   91.02%   -0.27%     
==========================================
  Files          75       79       +4     
  Lines        1102     1170      +68     
==========================================
+ Hits         1006     1065      +59     
- Misses         96      105       +9     

Flag	Coverage Δ
pytest	91.02% <86.76%> (-0.27%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
ensysmod/api/endpoints/energy_models.py	71.87% <71.87%> (ø)
ensysmod/api/api.py	100.00% <100.00%> (ø)
ensysmod/crud/__init__.py	100.00% <100.00%> (ø)
ensysmod/crud/energy_model.py	100.00% <100.00%> (ø)
ensysmod/model/__init__.py	100.00% <100.00%> (ø)
ensysmod/model/energy_model.py	100.00% <100.00%> (ø)
ensysmod/schemas/__init__.py	100.00% <100.00%> (ø)
ensysmod/schemas/energy_model.py	100.00% <100.00%> (ø)

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[github-actions]

Unit Test Results

  1 files  ±0    1 suites  ±0   15s ⏱️ -1s
59 tests +4  59 ✔️ +4  0 💤 ±0  0 ❌ ±0 

Results for commit 2770fd3. ± Comparison against base commit 87d42bd.