Change variable name to snake_case

[hhandoko]

Summary

An error is thrown when running this role in Vagrant v2.0.0 and Ansible v2.4.1.0. The main reason is that an existing variable, oracle-xe-test is using kebab-case convention.

I've renamed the variable to oracle_xe_test (i.e. snake_case), and it works as expected now.

Full error message below:

TASK [ansible-oraclexe : file] *************************************************
fatal: [oraclexe]: FAILED! => {"failed": true, "msg": "The conditional check 'oracle-xe-test' failed. The error was: error while evaluating conditional (oracle-xe-test): Unable to look up a name or access an attribute in template string ({% if oracle-xe-test %} True {% else %} False {% endif %}).\nMake sure your variable name does not contain invalid characters like '-': unsupported operand type(s) for -: 'dict' and 'StrictUndefined'\n\nThe error appears to have been in '/vagrant/scripts/ansible/roles/ansible-oraclexe/tasks/oracle-xe-test.yml': line 3, column 5, but may\nbe elsewhere in the file depending on the exact syntax problem.\n\nThe offending line appears to be:\n\n\n  - file: path=/tmp/test state=directory owner=oracle group=dba\n    ^ here\n"}
        to retry, use: --limit @/vagrant/scripts/ansible/playbook.retry