Merge #7818: Refactor script tests
dde46d3 Merge script_valid and script_invalid tests (Pieter Wuille)
009b503 Get rid of expect in script_tests as it's implied by scripterror (Pieter Wuille)
76da761 Make script_error a mandatory 4th field for script_tests (Pieter Wuille)
269281b Fix some misconstructed tests (Pieter Wuille)
d03e466 Fix formatting of NOPs for generated script tests (Pieter Wuille)
c7c6641 Fix JSON pretty printing in script_tests (Pieter Wuille)