Fix installed capacities plot function

[CarlosEpia]

Fixes #763.

Before merging into dev-branch, please make sure that

• [] the CHANGELOG.rst was updated.
• [] new and adjusted code is formated using black and isort.
• [] the Dataset-version is updated when existing datasets are adjusted.
• [] the branch was merged into the
  continuous-integration/run-everything-over-the-weekend-branch.
• [] the workflow is running successful in test mode.
• [] the workflow is running successful in Everything mode.

[CarlosEpia]

Hi @Alonsoju95 ,
Last week we experimented with some problems related to the plotting function you wrote. Therefore it was deleted from dev. We agreed with @ClaraBuettner on not using new libraries that are not part of setup.py now, in order to avoid dependencies problems in the future. I already made some changes to your branch, so please double-check that everything is working correctly. From now on you will be responsible for this PR, so please take a look at the checkpoints at the beginning of this page and proceed consequently. Let me know in case you have any questions.

[Alonsoju95]

@CarlosEpia Hi Carlos! Ok! I saw that the lines for the osm were erased, I understand it is because of the dependencies. Do I have to find another way to draw an osm map in the plot?

[CarlosEpia]

@CarlosEpia Hi Carlos! Ok! I saw that the lines for the osm were erased, I understand it is because of the dependencies. Do I have to find another way to draw an osm map in the plot?

It's not necessary. Just follow the steps to merge the PR. Keep in mind that you need to merge it into the current CI branch, but first I would check what's wrong with one of the Git checks (Codacy Static Code Analysis).