tests: Remove redundant regression tags

The tag is applied by the playbook that imports this one.

tests/ansible/regression/all.yml

@@ -1,30 +1,15 @@
 - import_playbook: issue_109__target_has_old_ansible_installed.yml
-  tags: regression
 - import_playbook: issue_113__duplicate_module_imports.yml
-  tags: regression
 - import_playbook: issue_118__script_not_marked_exec.yml
-  tags: regression
 - import_playbook: issue_122__environment_difference.yml
-  tags: regression
 - import_playbook: issue_140__thread_pileup.yml
-  tags: regression
 - import_playbook: issue_152__local_action_wrong_interpreter.yml
-  tags: regression
 - import_playbook: issue_152__virtualenv_python_fails.yml
-  tags: regression
 - import_playbook: issue_154__module_state_leaks.yml
-  tags: regression
 - import_playbook: issue_177__copy_module_failing.yml
-  tags: regression
 - import_playbook: issue_332_ansiblemoduleerror_first_occurrence.yml
-  tags: regression
 - import_playbook: issue_558_unarchive_failed.yml
-  tags: regression
 - import_playbook: issue_590__sys_modules_crap.yml
-  tags: regression
 - import_playbook: issue_591__setuptools_cwd_crash.yml
-  tags: regression
 - import_playbook: issue_615__streaming_transfer.yml
-  tags: regression
 - import_playbook: issue_655__wait_for_connection_error.yml
-  tags: regression