This change corrects problems reported by the `yamllint` linter.
Since key duplication problems were removed in 4d48711, this commit
mainly fixes trailing spaces and extra empty lines at beginning/end of
files.
If the facts returned by setup included strings that
had double quotes in them, the asserts in test_gathering_facts.yml
would fail with errors like:
"The conditional check '\"[{u'mounts': {u'options':
u'rw,context=\"system_u:\"'}}]\" != \"UNDEF_HW\"' failed. The error was:
template error while templating string: expected token 'end of statement
block', got 'system_u'. String: {% if \"[{u'mounts': {u'options':
u'rw,context=\"system_u:\"'}}]\" != \"UNDEF_HW\" %} True {% else %}
False {% endif %}"
For one example, if mount facts returned an 'options' field that
included double quoated selinux context ids, the test would fail.
Fix is removing the double quoting in the assert 'that:' lines,
and removing the unneeded double curly brackets.
