Fix ECO images - rollback buildbot.tac

Failing builds, tac is missing
https://buildbot.mariadb.org/#/builders/237

Author: RazvanLiviuVarzaru

dockerfiles/buildbot.tac

@@ -0,0 +1,39 @@
+import fnmatch
+import os
+import sys
+
+from twisted.application import service
+from twisted.python.log import FileLogObserver
+from twisted.python.log import ILogObserver
+
+from buildbot_worker.bot import Worker
+
+# setup worker
+basedir = os.path.abspath(os.path.dirname(__file__))
+application = service.Application('buildbot-worker')
+
+
+application.setComponent(ILogObserver, FileLogObserver(sys.stdout).emit)
+# and worker on the same process!
+buildmaster_host = os.environ.get("BUILDMASTER", 'localhost')
+port = int(os.environ.get("BUILDMASTER_PORT", 9989))
+workername = os.environ.get("WORKERNAME", 'docker')
+passwd = os.environ.get("WORKERPASS")
+
+# delete the password from the environ so that it is not leaked in the log
+blacklist = os.environ.get("WORKER_ENVIRONMENT_BLACKLIST", "WORKERPASS").split()
+for name in list(os.environ.keys()):
+    for toremove in blacklist:
+        if fnmatch.fnmatch(name, toremove):
+            del os.environ[name]
+
+keepalive = 600
+umask = None
+maxdelay = 300
+allow_shutdown = None
+maxretries = 10
+
+s = Worker(buildmaster_host, port, workername, passwd, basedir,
+           keepalive, umask=umask, maxdelay=maxdelay,
+           allow_shutdown=allow_shutdown, maxRetries=maxretries, unicode_encoding='utf-8')
+s.setServiceParent(application)