this commit fixes two bugs and adds regression tests.
when getting healthcheck values from an image, if the image does not
have a timeout defined, this resulted in a 0 value for timeout. The
default as described in the man pages is 30s.
when inspecting a container with a healthcheck command, a customer
observed that the &, <, and > characters were being converted into a
unicode escape value. It turns out json marshalling will by default
coerce string values to ut8.
Fixes: bz2028408
Signed-off-by: Brent Baude <bbaude@redhat.com>
