Fix bug where paramsAreBad doesn't update string

Fix bug where paramsAreBad doesn't update string

Replaced the string parameter with a StringBuilder so that the modified
version can be accessed outside the method, since strings are immutable.
Added null check for properties. Removed trim on properties in case the
property is null. Added junit to test that the modified StringBuilder can
be read outside the paramsAreBad method.

Issue-ID: POLICY-492
Change-Id: I0550e9d639cbbcc876e6aafb84f6e9a363b653ff
Signed-off-by: Temoc Rodriguez <cr056n@att.com>