test: record the jsc backend's new pass

 links and runs after the C ABI port, and reports the same single
new pass the sys-jsc leg did. The vendored-WebKit backend cannot be built
outside CI, so this mirrors the sys-jsc baseline, which the two share
line-for-line.

Author: bartlomieju

tests/status/baselines/jsc/rusty_v8.txt

@@ -1,6 +1,6 @@
 # Baseline: tests that PASS for backend=jsc suite=rusty_v8.
 # Ratchet — CI goes red if any of these regress. Add new passes here
-# (run.mjs --update). 46 passing. DO NOT hand-sort; the
+# (run.mjs --update). 47 passing. DO NOT hand-sort; the
 # harness keeps this sorted + unique.
 rv8_slots::context_slots
 rv8_slots::dropped_context_slots_on_kept_context
@@ -46,5 +46,6 @@ rv8_test_api::inspector_can_dispatch_method
 rv8_test_api::inspector_string_buffer
 rv8_test_api::inspector_string_view
 rv8_test_api::latin1_to_utf8
+rv8_test_api::v8_string_is_not_sync
 rv8_test_simple_external::test_simple_external::test
 rv8_test_single_threaded_default_platform::single_threaded_default_platform