Update parameter description for the result

Author: YaSuenag

substratevm/src/org.graalvm.polyglot.nativeapi/src/org/graalvm/polyglot/nativeapi/PolyglotNativeAPI.java

@@ -467,7 +467,7 @@ public static PolyglotStatus poly_context_close(PolyglotIsolateThread thread, Po
                     " @param language_id the language identifier.",
                     " @param name_utf8 given to the evaluate source code.",
                     " @param source_utf8 the source code to be evaluated.",
-                    " @param result <code>poly_value</code> that is the result of the evaluation.",
+                    " @param result <code>poly_value</code> that is the result of the evaluation. You can pass <code>NULL</code> if you just want to evaluate the source and you can ignore the result.",
                     " @return poly_ok if all works, poly_generic_error if there is a failure.",
                     " @see org::graalvm::polyglot::Context::eval",
                     " @since 19.0",
@@ -573,6 +573,7 @@ public static PolyglotStatus poly_value_can_execute(PolyglotIsolateThread thread
                     " @param value to be executed.",
                     " @param args array of poly_value.",
                     " @param args_size length of the args array.",
+                    " @param result <code>poly_value</code> that is the result of the execution. You can pass <code>NULL</code> if you just want to execute the source and you can ignore the result.",
                     " @return poly_ok if all works, poly_generic_error if the underlying context was closed, if a wrong ",
                     "         number of arguments was provided or one of the arguments was not applicable, if this value cannot be executed,",
                     " and if a guest language error occurred during execution.",