stbt-templatematch: create MatchResult with `image` to avoid warning
stbt-templatematch: create MatchResult with `image` to avoid warning

Commit f51f6487 introduced the `image` parameter to the MatchResult class,
and added a DeprecationWarning which was invoked whenever a MatchResult
was created without `image` being set. However, the `image` parameter
wasn't added to stbt-templatematch, and so the verbose DeprecationWarning
came up every time you ran it.

Note that I could have added `image=template_image` and it would have
been valid, however this would print out "image=<Custom Image>", which
is pretty useless.

martynjarvis/stb-tester,stb-tester/stb-tester,LewisHaley/stb-tester,martynjarvis/stb-tester,stb-tester/stb-tester,wmanley/stb-tester,LewisHaley/stb-tester,martynjarvis/stb-tester,martynjarvis/stb-tester,LewisHaley/stb-tester,LewisHaley/stb-tester,martynjarvis/stb-tester,wmanley/stb-tester,martynjarvis/stb-tester,martynjarvis/stb-tester,LewisHaley/stb-tester,wmanley/stb-tester,LewisHaley/stb-tester,stb-tester/stb-tester,LewisHaley/stb-tester,wmanley/stb-tester,stb-tester/stb-tester,wmanley/stb-tester