Bring out a test base for scaling tests

[IlyaPechersky]

If I understood the request from #1264 correctly, we need to reject files with binary code.

To do this, I added a new check in checks.xml , and also added a test with a new one.a java file with binary code.

[pnatashap]

@IlyaPechersky File with tests become too long, please create one file in addition
you can use this command locally to check if all is good

mvn -B install -Pqulice

[yegor256]

@IlyaPechersky actually, #1264 was about something else: we want Qulice to ignore binary files (like PNG, JPEG, or PDF) and don't complain about them. However, your pull request is also interesting, I think we should make it good and then merge.

[IlyaPechersky]

@yegor256 I realized, it turns out I was really solving another problem)
Now I have separated the common methods and the matcher class into a package so as not to duplicate them in the test classes.
Thus, there are now two types of tests: one checks the content of files, the other meta information.

[yegor256]

@pnatashap please, help us review this

[IlyaPechersky]

@pnatashap do you have any other issues?

[IlyaPechersky]

@yegor256, Are there any more issues?

[yegor256]

@pnatashap can you please take a look one more time?

[IlyaPechersky]

In this request, two problems were solved at once: making a test base and adding tests for content in files, so for now I have left the solution to only one problem - making a test base

[IlyaPechersky]

@yegor256 I left only one problem

Is there something else to add?

[IlyaPechersky]

@yegor256 Thanks for the article! Replaced inheritance with a utility class

[yegor256]

@IlyaPechersky utility classes are also a bad idea in OOP: https://www.yegor256.com/2014/05/05/oop-alternative-to-utility-classes.html