Separate some 255 exit codes that are not ssh errors

The ssh connection plugin is overzealous in thinking that error code 255
can only come from ssh.  Python can return 255 in some circumstances and
error from php does as well.

changelogs/fragments/fix-255-exit-code.yaml

@@ -0,0 +1,6 @@
+---
+bugfixes:
+- 'The ssh connection plugin was categorizing all 255 exit statuses as an ssh
+  error but modules can return exit code 255 as well.  The connection plugin
+  has now been changed to know that certain instances of exit code 255 are not
+  ssh-related.  (https://github.com/ansible/ansible/pull/41716)'

lib/ansible/plugins/connection/ssh.py

@@ -297,6 +297,11 @@ except ImportError:
     display = Display()
 
 
+NOT_SSH_ERRORS = ('Traceback (most recent call last):',  # Python-2.6 when there's an exception
+                                                         # while invoking a script via -m
+                  'PHP Parse error:',  # Php always returns error 255
+                  )
+
 SSHPASS_AVAILABLE = None
 
 
@@ -333,7 +338,7 @@ def _ssh_retry(func):
                     display.vvv(return_tuple, host=self.host)
                     # 0 = success
                     # 1-254 = remote command return code
-                    # 255 = failure from the ssh command itself
+                    # 255 could be a failure from the ssh command itself
                 except (AnsibleControlPersistBrokenPipeError) as e:
                     # Retry one more time because of the ControlPersist broken pipe (see #16731)
                     cmd = args[0]
@@ -344,10 +349,19 @@ def _ssh_retry(func):
                     display.vvv(u"RETRYING BECAUSE OF CONTROLPERSIST BROKEN PIPE")
                     return_tuple = func(self, *args, **kwargs)
 
-                if return_tuple[0] != 255:
-                    break
-                else:
-                    raise AnsibleConnectionFailure("Failed to connect to the host via ssh: %s" % to_native(return_tuple[2]))
+                if return_tuple[0] == 255:
+                    SSH_ERROR = True
+                    for signature in NOT_SSH_ERRORS:
+                        if signature in return_tuple[1]:
+                            SSH_ERROR = False
+                            break
+
+                    if SSH_ERROR:
+                        raise AnsibleConnectionFailure("Failed to connect to the host via ssh: %s"
+                                                       % to_native(return_tuple[2]))
+
+                break
+
             except (AnsibleConnectionFailure, Exception) as e:
                 if attempt == remaining_tries - 1:
                     raise