Fix typo in comment in idl.h (#8907)

Co-authored-by: Justin Davis <jtdavis777@gmail.com>

include/flatbuffers/idl.h

diff --git a/include/flatbuffers/idl.h b/include/flatbuffers/idl.h
index 5a63fa7..06f93f3 100644
--- a/include/flatbuffers/idl.h
+++ b/include/flatbuffers/idl.h
@@ -223,7 +223,7 @@
   uint16_t fixed_length;  // only set if t == BASE_TYPE_ARRAY
 };
 
-// Represents a parsed scalar value, it's type, and field offset.
+// Represents a parsed scalar value, its type, and field offset.
 struct Value {
   Value()
       : constant("0"),