IdentifierName rejects m-failsafe-p default inclusion patterns

By default, the Maven Failsafe plugin relies on a set of file name patterns to determine which test classes to include. This is the [``](https://maven.apache.org/surefire/maven-failsafe-plugin/integration-test-mojo.html#includes) option, and its default values are

- `**/IT*.java`
- `**/*IT.java`
- `**/*ITCase.java`

In v2.36.0, the `IdentifierName` check (which I'm unreasonably excited about!) accurately detects those names as being [in violation](https://google.github.io/styleguide/javaguide.html#s5.3-camel-case).

Unfortunately, for a user wishing to take advantage of Failsafe, working around this is a bit cumbersome; it seems they can...

- ... **not run Error Prone on test code at all**, but I would like to.
- ... **change `` to any compliant non-default value**, but that introduces non-standard behaviour for dubious reasons.
- ... **use `-XepOpt:IdentifierName:AllowInitialismsInTypeName=true`**, but actually, that allows a name like `XMLHTTPRequest` that is specifically called out as in violation, and incidentally, is exactly the sort of situations I see people struggle with the most.
- ... **suppress each violation**, which I personally consider the correct response but a noisy and tiresome one.

Every option is possible but all of them carry friction.

The behaviour I would most like to see is that `IdentifierName` automagically did not flag these cases so the defaults Just Work™. But Error Prone cannot know which arbitrary patterns I might have set in my own ``, so any support for this is bound to be either inflexible or complex. Correspondingly, I would suggest that **`IdentifierName` should _at most_ allow Failsafe's default `` values**

A more flexible approach is a new option, `-XepOpt:IdentifierName:MyBikeshed=*IT,*MXBean`, which passes a set of patterns to `IdentifierName` to allow.

See also #4776.

```
$ ./mvnw clean test-compile -DepFlags='-XepDisableAllChecks -Xep:IdentifierName:ERROR'
[INFO] Scanning for projects...
[INFO]
...
[INFO] -------------------------------------------------------------
[ERROR] COMPILATION ERROR :
[INFO] -------------------------------------------------------------
[ERROR] /.../src/test/java/example/ITFoo.java:[1,8] [IdentifierName] Classes should be named in UpperCamelCase, with acronyms treated as words (https://google.github.io/styleguide/javaguide.html#s5.3-camel-case); did you mean 'ItFoo'?
(see https://google.github.io/styleguide/javaguide.html#s5.2-specific-identifier-names)
[ERROR] /.../src/test/java/example/FooIT.java:[3,8] [IdentifierName] Classes should be named in UpperCamelCase, with acronyms treated as words (https://google.github.io/styleguide/javaguide.html#s5.3-camel-case); did you mean 'FooIt'?
(see https://google.github.io/styleguide/javaguide.html#s5.2-specific-identifier-names)
[ERROR] /.../src/test/java/example/FooITCase.java:[3,8] [IdentifierName] Classes should be named in UpperCamelCase, with acronyms treated as words (https://google.github.io/styleguide/javaguide.html#s5.3-camel-case); did you mean 'FooItCase'?
(see https://google.github.io/styleguide/javaguide.html#s5.2-specific-identifier-names)
```