Dedicated log marker for invalid txs removed from the txpool

[fab-10]

PR description

Transactions that during block creation are found to be invalid are removed from the pool, and could be difficult to retrieve the content of the tx, so if needed for debug, with this PR is possible to enable the log the RLP of the invalid tx, along with some other info, these log lines have the marker INVALID_TX_REMOVED and the following fields, that can be used to format the log line as required:

• txhash hash of the tx
• txlog human readable log of the tx
• reason why the tx was invalid
• txrlp the RLP encoding of the tx

Log4j2 example configuration to enable the invalid tx log:

<?xml version="1.0" encoding="UTF-8"?>
<Configuration monitorInterval="30" status="INFO">
  <Properties>
    <Property name="root.log.level">INFO</Property>
  </Properties>
  <Appenders>
    <Console name="Console">
      <PatternLayout pattern="%d{yyyy-MM-dd HH:mm:ss.SSSZZZ} | %t | %-5level | %c{1} | %msg%n"/>
    </Console>
    <Routing name="Router">
      <Routes pattern="$${event:Marker}">
        <Route key="INVALID_TX_REMOVED">
          <Console name="ConsoleITR" target="SYSTEM_OUT">
            <PatternLayout pattern="Invalid tx removed:%X{txlog}, reason:%X{reason}; RLP={%X{txrlp}}}%n"/>
          </Console>
        </Route>
        <Route ref="Console"/>
      </Routes>
    </Routing>
  </Appenders>
  <Loggers>
        <Logger additivity="false" name="org.hyperledger.besu.ethereum.eth.transactions">
            <AppenderRef ref="Router"/>
        </Logger>
    <Root level="${sys:root.log.level}">
      <AppenderRef ref="Console"/>
    </Root>
  </Loggers>
</Configuration>

Fixed Issue(s)

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• Checked out our contribution guidelines?
• Considered documentation and added the doc-change-required label to this PR if updates are required.
• Considered the changelog and included an update if required.
• For database changes (e.g. KeyValueSegmentIdentifier) considered compatibility and performed forwards and backwards compatibility tests

Locally, you can run these tests to catch failures early:

• unit tests: ./gradlew build
• acceptance tests: ./gradlew acceptanceTest
• integration tests: ./gradlew integrationTest
• reference tests: ./gradlew ethereum:referenceTests:referenceTests

[jflo]

The size of the tracelog and the raw data gives me concerns about this as a griefing vector. What if we separated those two fields into a debug call and leave hash and reason in at info?

[fab-10]

If your concern is about the size of the logged message, then the way I set up the log with the marker and key-value, is indeed to avoid that this line is logged by default, and you need to explicitly configure log4j to enabled this log, and you can choose which of the keys to log.

[jflo]

Same separation advice as above.

[jflo]

love Log4j use here, we should probably add a section on how to use this to https://besu.hyperledger.org/public-networks/how-to/monitor/logging