[sprout][fixtures] Annotate some fixtures
--- This PR is an example of how to update fixture to add sprout annotations. Running with `yarn sprout --verbose --filter` shows the fixture outputs. ``` PASS array-access-assignment ok [[2],[[2],[],[3]]] PASS array-expression-spread ok [0,1,2,3,null,4,5,6,"z"] PASS array-map-frozen-array ok [[],[]] PASS array-map-mutable-array-mutating-lambda ok [[],[]] PASS array-pattern-params ok [{"a":"val1"},{"b":"val2"}] PASS array-properties ok {"a":[[1,2],2,"hello"],"x":3,"y":"[[ function params=1 ]]","z":"[[ function params=1 ]]"} PASS array-property-call ok {"a":[1,2,"hello",42],"x":4,"y":1} PASS assignment-expression-computed ok [7] PASS assignment-expression-nested-path ok {"b":{"c":6}} PASS capturing-func-mutate-2 ok {"a":2} PASS capturing-function-alias-computed-load-2 ok "val2" PASS capturing-function-alias-computed-load-4 ok "val2" ```