Remove hardcoded LOGNAME for ansible-playbook

This meant bubblewrap needed to have a zuul user on the host system,
which when gathering facts on localhost would cause an ansible
failure.  Additionally, this no longer is needed because our logging
is now handled by zuul_stream.

Change-Id: I75cd050e26438dbe6d47ff216ffe6e08b9687aca
Signed-off-by: Paul Belanger <pabelanger@redhat.com>
diff --git a/zuul/executor/server.py b/zuul/executor/server.py
index d504cdf..a3bea9b 100644
--- a/zuul/executor/server.py
+++ b/zuul/executor/server.py
@@ -1315,7 +1315,6 @@
     def runAnsible(self, cmd, timeout, config_file, trusted):
         env_copy = os.environ.copy()
         env_copy.update(self.ssh_agent.env)
-        env_copy['LOGNAME'] = 'zuul'
         env_copy['ZUUL_JOB_OUTPUT_FILE'] = self.jobdir.job_output_file
         env_copy['ZUUL_JOBDIR'] = self.jobdir.root
         pythonpath = env_copy.get('PYTHONPATH')
@@ -1415,9 +1414,6 @@
 
     def runAnsiblePlaybook(self, playbook, timeout, success=None,
                            phase=None, index=None):
-        env_copy = os.environ.copy()
-        env_copy['LOGNAME'] = 'zuul'
-
         if self.executor_server.verbose:
             verbose = '-vvv'
         else: