JavadocVariable: new property 'accessModifiers' as substitution of 'scope' and 'excludeScope'

[romani]

JavadocVariable - https://checkstyle.org/config_javadoc.html#JavadocVariable
https://checkstyle.org/checks/javadoc/javadocvariable.html#JavadocVariable

Example of user confusion and problem with such type - #3183

have have issues with Scope enumeration
we should switch to AccessModifier here like we did for ParameterNameCheck.
New property need t be created as substitution to 2 old properties.
https://checkstyle.org/property_types.html#AccessModifierOption.5B.5D
https://checkstyle.org/config_naming.html#ParameterName_Properties

TODO: after completion close #3183

local classes (named classes in methods or any other blocks) and antonymous classes should be skipped by Check for validation, see details at #13749

---

Migration notes:

    <module name="JavadocVariable">
       <property name="severity" value="warning"/>
-      <property name="scope" value="protected"/>
+      <property name="accessModifiers" value="protected"/>
     </module>

There might be few more violations, user needs to fix the or suppress.
Examples of migration:

• build-tools PR
• xwiki-commons PR
• xwiki-platforms PR

[romani]

@kkoutsilis , thanks a lot for making it happen!!!