Fix-11102 by giving user option to add a bst style preview to available

[sahilsekr42]

I've tried to fix #11102 by adding a button which may be used to add the selected bst files to the available styles and tested it to work although I think for preview to function well bstvm should be used not sure how. Would like some guidence . After it works as expected may be documentation can be modified.

Mandatory checks

• Change in CHANGELOG.md described in a way that is understandable for the average user (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 developer's documentation: Is the information available and up to date? If not, I outlined it in this pull request.
• Checked documentation: Is the information available and up to date? If not, I created an issue at https://github.com/JabRef/user-documentation/issues or, even better, I submitted a pull request to the documentation repository.

[Siedlerchr]

You can click on the details next to the failing test and you will see where the error is.

[subhramit]

To conform to JabRef's Checkstyle, set up the following:
https://devdocs.jabref.org/getting-into-the-code/guidelines-for-setting-up-a-local-workspace/intellij-13-code-style.html

To pass the OpenRewrite check, run gradle rewriteRun.
Info: https://docs.openrewrite.org/

[subhramit]

Your unit test error log says:

Task :compileJava
/home/runner/work/jabref/jabref/src/main/java/org/jabref/gui/preferences/preview/PreviewTab.java:123: error: cannot find symbol
        previewViewer.setEntry(TestEntry.getTestEntry());
        ^
  symbol:   variable previewViewer
  location: class PreviewTab

You're probably using an undeclared symbol.

(To check, click on "Details").

[subhramit]

Also, add a changelog line.
Refer https://devdocs.jabref.org/contributing.html (Formal requirements for a pull request).

[subhramit]

Hey, may I know why you closed the PR?
By the way, thanks for moving forward. I know, the first PR can be overwhelming, but this will get you used to all the formalities and you won't face much difficulties afterwards.
I also suggest you join the Gitter chat where you can ask miscellaneous queries.

[sahilsekr42]

okay , i,m joining btw i closed it because of my poor understanding of how pull requests and automated tests work ( glad to learn now )

[subhramit]

okay , i,m joining btw i closed it because of my poor understanding of how pull requests and automated tests work ( glad to learn now )

No issues at all, ask as many questions as you want. We'll be there to help.

[koppor]

@sahilsekr42 You can reopen the PR by clicking on "Reopen", can't you?

[koppor]

Ah, follow-up PR is #11234.