Replace <p> in localization by \n

[koppor]

Triggered by #7232 (comment), I saw that we did not cover the RuntimeExceptions by test cases. This PR adds them.

This PR also adds a check for \n in Localization strings. I do not now anything about handling <br> and \n in JavaFX. It seems, that we cannot have line breaks in either way. Maybe, I should document that somewhere.

• Change in CHANGELOG.md described (if applicable)
• Tests created for changes (if applicable)
• Manually tested changed features in running JabRef (always required)
• Screenshots added in PR description (for UI changes)
• Checked documentation: Is the information available and up to date? If not created an issue at https://github.com/JabRef/user-documentation/issues or, even better, submitted a pull request to the documentation repository.

[Siedlerchr]

I think only in the search the formatting html tool tip are replaced with javafx formatting for bold etc
Line breaks using \n must be outside the Localization.lang calls
e.g Localization.lang("first line") +\n + Localization.lang("second line")

[Siedlerchr]

But according to this thread https://stackoverflow.com/a/10285574/3450689

They should also work in the keys

[koppor]

I think only in the search the formatting html tool tip are replaced with javafx formatting for bold etc
Line breaks using \n must be outside the Localization.lang calls
e.g Localization.lang("first line") +\n + Localization.lang("second line")

We should never split up lines of localizations into different keys. Thank you for the \n pointer in the other message. I'll update the PR accordingly.

[koppor]

Intermediate report: We had <p> hardcorded and replaced it by \n at

jabref/src/main/java/org/jabref/gui/search/GlobalSearchBar.java

Line 333 in afdb194

genericDescription = genericDescription.replace("<p>", "\n");

.

I am trying to dig deeper there.

[Siedlerchr]

We should only keep the HTML tags for bold, italic and monospaced (See ToolTipTextUtil) because otherwise we can't indicate if the text is bold or not. As Javafx does not have HTML support, we must then use a TextFlow element with the CSS.

[tobiasdiez]

It may also worthwhile to explore if the language keys still need to be escaped at all. If I remember correctly, that's actually not the case any longer.

[koppor]

Current result:

[calixtus]

Two questions.
Everything else looks good enough to me. ;-)

[calixtus]

Btw.: Error: eckstyle] [ERROR] /home/runner/work/jabref/jabref/src/test/java/org/jabref/gui/search/ContainsAndRegexBasedSearchRuleDescriberTest.java:3:8: Unused import - java.util.Arrays. [UnusedImports]

[calixtus]

ManageStudyDefinitionView.java