VariableHasSpacesRule testing was limited to ensuring that the number of
error was matching an expected number. This could have potential
limitation where for example a commit prevents an real linting error
from being raised and in the same time raises an invalid one.

This commit aims at improving this rule's testing by ensuring that
errors are raised only on a controlled set of lines.

Related to: ansible#1671

This commit adds 4 new tasks in example playbook used for
VariableHasSpacesRule testing.

One of these rule is a nested multiline JSON object which has its
opening and closing brackets spanned on different lines. And this rule
raises false positive error.

Related to ansible#1671

When using a nested JSON object spanned on multiple lines in a Jinja2
context ansible-lint raises a false positive E206 error.

This commit extends the regex in charge of excluding false positive JSON
objects so that it handles multiline matching.

Fixes ansible#1671

…sitive