Memory Leak due to JSStringRelease not called in multiple places in J…

…SCRuntime.cpp (#25884)

Summary:
Memory Leak due to JSStringRelease not called in multiple places in JSCRuntime.cpp
Issue: #25664
Reproducible repo: https://github.com/bhandarijiwan/memory_issue_repro

## Changelog
[JSC] [JSCRuntime.cpp] - Added missing JSStringRelease calls in missing places
Pull Request resolved: #25884

Test Plan: Tested that is no memory leak with various NativeModule to JS call flows

Reviewed By: JoshuaGross

Differential Revision: D16928985

Pulled By: TheSavior

fbshipit-source-id: 65ce15ae32482d0db39bad7e22a2fed9ee04f230

ReactCommon/jsi/JSCRuntime.cpp

@@ -630,7 +630,9 @@ jsi::String JSCRuntime::createStringFromUtf8(
     size_t length) {
   std::string tmp(reinterpret_cast<const char*>(str), length);
   JSStringRef stringRef = JSStringCreateWithUTF8CString(tmp.c_str());
-  return createString(stringRef);
+  auto result = createString(stringRef);
+  JSStringRelease(stringRef);
+  return result;
 }
 
 std::string JSCRuntime::utf8(const jsi::String& str) {