KREST-10243 Add custom-request-logging to kafka-rest, and log error-codes for when various rate-limiters are triggered

[msn-tldr]

Following categories of changes are introduced in this PR.

1. The new request-logger that will log custom metadata as part of the request-log.

• Adds CustomLog.java, as a new Jetty request-logger, that also logs configured request-attributes.
  Example:
  Existing
  GET /kafka/v3/clusters/lkc-foobar/consumer-groups/foobar/lags HTTP/1.1" 429 408 "-" "Mozilla/5.0 (Windows NT; Windows NT 10.0; en-US) WindowsPowerShell/5.1.14393.5582
  Vs NOTE the new log has the error-code 429007 at the end, which is error-code defined in RateLimitExceededException.java class.
  GET /kafka/v3/clusters/lkc-foobar/consumer-groups/foobar/lags HTTP/1.1" 429 408 "-" "Mozilla/5.0 (Windows NT; Windows NT 10.0; en-US) WindowsPowerShell/5.1.14393.5582 429007

2. Populate the relevant meta-data on request. This requires new request-attribute i.e. REST_ERROR_CODE to be populated when a rate-limit is being triggered. All rate-limiters, when triggered have a corresponding "error-code" in request-log, this logic is tested in RestCustomRequestLogIntegrationTest.java.

• RateLimitExceededException.java has the error-codes that will be logged when rate-limit is triggered.
• GlobalDosFilterListener.java & PerConnectionDosfilterListener.java are DosFilter.Listeners that on global & per-ip Jetty rate-limiters populate request-attribute needed for logging.
• FixedCostRateLimitRequestFilter has changes to log error-code when Jersey request rate-limits are triggered.
• Relevant changes to ProduceRatelimiters to log error-code when produce rate limits are triggered.
• Tests

3. This new custom-logger can be toggled on/off via use.custom.request.logging. By default it's ON.

[trnguyencflt]

@msn-tldr could you sync this branch with master so that the build can pass? as rest-utils PR has been merged.

[msn-tldr]

@trnguyencflt the build-failure is not do with rest-utils but very checkstyle issue -
ERROR] /home/jenkins/workspace/po_PR_builder_kafka-rest_PR-1168/kafka-rest/src/test/java/io/confluent/kafkarest/resources/v3/ProduceActionTest.java:40:8: Unused import - com.google.api.Http. [UnusedImports]

Weirdly, the import is not in my local repo, only here. When i try to update the remote repo(even forcefully), github thinks everything is upto date, and so the unused import doesn't go away.

Edit: Now fixed. Also had to rebase off master, since the version was bumped from 7.5.0 to 7.6.0, to pick latest build of rest-utils, and compile successfully.

[trnguyencflt]

LGTM 👍