I have a PhabricatorRepositoryMercurialCommitChangeParserWorker which has already failed thousands of times (the error log is below). Is there a way to abort this task instead of having it retried every minute or so?
```
[2015-09-14 13:28:33] EXCEPTION: (PhutilProxyException) Error while executing Task ID 250629. {>} (AphrontCharacterSetQueryException) Attempting to construct a query using a non-utf8 string when utf8 is expected. Use the `%B` conversion to escape binary strings data. at [<phutil>/src/aphront/storage/connection/mysql/AphrontBaseMySQLDatabaseConnection.php:334] arcanist(head=stable, ref.master=d54cb072facd, ref.stable=316858315950), phabricator(head=stable, ref.master=bdd0e340ff91, ref.stable=875a99524f8b), phutil(head=stable, ref.master=fffe7e4ef4c8, ref.stable=d82ea11b139d) #0 <#2> AphrontBaseMySQLDatabaseConnection::validateUTF8String(string) called at [<phutil>/src/aphront/storage/connection/mysql/AphrontMySQLiDatabaseConnection.php:10] #1 <#2> AphrontMySQLiDatabaseConnection::escapeUTF8String(string) called at [<phutil>/src/xsprintf/qsprintf.php:178] #2 <#2> xsprintf_query(AphrontMySQLiDatabaseConnection, string, integer, string, integer) called at [<phutil>/src/xsprintf/xsprintf.php:70] #3 <#2> xsprintf(string, AphrontMySQLiDatabaseConnection, array) called at [<phutil>/src/xsprintf/qsprintf.php:64] #4 <#2> qsprintf(AphrontMySQLiDatabaseConnection, string, string, string) called at [<phabricator>/src/applications/repository/worker/commitchangeparser/PhabricatorRepositoryCommitChangeParserWorker.php:58] #5 <#2> PhabricatorRepositoryCommitChangeParserWorker::lookupOrCreatePaths(array) called at [<phabricator>/src/applications/repository/worker/commitchangeparser/PhabricatorRepositoryMercurialCommitChangeParserWorker.php:255] #6 <#2> PhabricatorRepositoryMercurialCommitChangeParserWorker::parseCommitChanges(PhabricatorRepository, PhabricatorRepositoryCommit) called at [<phabricator>/src/applications/repository/worker/commitchangeparser/PhabricatorRepositoryCommitChangeParserWorker.php:30] #7 <#2> PhabricatorRepositoryCommitChangeParserWorker::parseCommit(PhabricatorRepository, PhabricatorRepositoryCommit) called at [<phabricator>/src/applications/repository/worker/PhabricatorRepositoryCommitParserWorker.php:44] #8 <#2> PhabricatorRepositoryCommitParserWorker::doWork() called at [<phabricator>/src/infrastructure/daemon/workers/PhabricatorWorker.php:91] #9 <#2> PhabricatorWorker::executeTask() called at [<phabricator>/src/infrastructure/daemon/workers/storage/PhabricatorWorkerActiveTask.php:162] #10 <#2> PhabricatorWorkerActiveTask::executeTask() called at [<phabricator>/src/infrastructure/daemon/workers/PhabricatorTaskmasterDaemon.php:22] #11 PhabricatorTaskmasterDaemon::run() called at [<phutil>/src/daemon/PhutilDaemon.php:183] #12 PhutilDaemon::execute() called at [<phutil>/scripts/daemon/exec/exec_daemon.php:125]
```