add testcase for #15937 (#15933)

* test for issue #15624 and PR #15915 for patch #13823

* Update thashes.nim

no need mention PR #15915, fixed in #15937

* rebase to devel(issue maybe fixed), ignore ouputs

* Apply suggestions from code review

Co-authored-by: flywind <43030857+xflywind@users.noreply.github.com>

tests/stdlib/thashes.nim

@@ -1,3 +1,7 @@
+discard """
+  targets: '''c c++ js'''
+"""
+
 import hashes
 
 block hashes:
@@ -13,8 +17,10 @@ block hashes:
   # "VM and runtime should make the same hash value (hashWangYi1)"
   block:
     const wy123 = hashWangYi1(123)
+    doAssert wy123 != 0
     doAssert hashWangYi1(123) == wy123
 
+
   # "hashIdentity value incorrect at 456"
   block:
     doAssert hashIdentity(456) == 456