Non clean backport of #16959 from 8.x to 8.16 (which is a non clean backport of #16576 to 8.x)

Changes respect to 8.x:

• in 8.x the with_deprecated_alias receives also a parameter specifying the version where the setting is removed. In this case we removed the extra parameter to the method

  logstash/logstash-core/lib/logstash/environment.rb

  Line 79 in a0378c0

  Setting::SettingString.new("api.environment", "production").with_deprecated_alias("http.environment", "9"),

• fixed the test removing the check for the remove version

  logstash/logstash-core/spec/logstash/settings/setting_with_deprecated_alias_spec.rb

  Line 157 in a0378c0

  expect(events[1]).to include("version 9")

Reimplements LogStash::Setting::String Ruby setting class into the org.logstash.settings.SettingString and exposes it through java_import as LogStash::Setting::SettingString. Updates the rspec tests in two ways:

• logging mock is now converted to real Log4J appender that spy log line that are later verified
• verifies java.lang.IllegalArgumentException instead of ArgumentError is thrown because the kind of exception thrown by Java code, during verification.

• Fixed the rename of NullableString to SettingNullableString

• Fixed runner test to use real spy logger from Java Settings instead of mock test double

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• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have made corresponding change to the default configuration files (and/or docker env variables)
• I have added tests that prove my fix is effective or that my feature works

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