ln() before text uses font_htight, fixes #937

[gmischler]

e.g. Fixes #937
Checklist:

• The GitHub pipeline is OK (green),
  meaning that both pylint (static code analyzer) and black (code formatter) are happy with the changes of this PR.
• A unit test is covering the code added / modified by this PR
• This PR is ready to be merged
• In case of a new feature, docstrings have been added, with also some documentation in the docs/ folder
• A mention of the change is present in CHANGELOG.md

The modified test files typically use a ln() in a loop.

By submitting this pull request, I confirm that my contribution is made under the terms of the GNU LGPL 3.0 license.

[gmischler]

Apparently a new pylint version has removed 'implicit-str-concat' from the defaults...

edit:
Alright, so apparently just the rules have changed:
Implicit concatenation is considered ok when the strings are the only thing between a set of parens.
I just fixed all instances in this manner, removed the respective pylint control comments, and packed that chance onto this PR.

[gmischler]

Ok, so since this is quite a trivial change which has already been discussed in #937, it passes all the tests (except for the silly large-text timing), and the pylint related changes will help all other PRs to pass their tests, I'm not going to wait for reviews and just send it.